By American Society of Clinical Oncology (ASCO)
The podcast currently has 32 episodes available.
JCO PO author Dr. Alok A. Khorana, MD, FASCO, Professor of Medicine, Cleveland Clinic and Case Comprehensive Cancer Center, shares insights into the JCO PO article, “Molecular Differences With Therapeutic Implications in Early-Onset Compared With Average-Onset Biliary Tract Cancers.” Host Dr. Rafeh Naqash and Dr. Khorana discuss how multiomic analysis shows higher FGFR2 fusions and immunotherapy marker variations in early-onset biliary cancer.
TRANSCRIPT
Dr. Rafeh Naqash: Hello, and welcome to JCO Precision Oncology Conversations, where we bring you engaging conversations with authors of clinically relevant and highly significant JCO POarticles. I'm your host, Dr. Rafeh Naqash, Podcast Editor for JCO Precision Oncology and Assistant Professor at the OU Health Stephenson Cancer Center at the University of Oklahoma.
Today, we are joined by Dr. Alok A. Khorana, Professor of Medicine at the Cleveland Clinic and Case Comprehensive Cancer Center, and also the Senior Author of the JCO Precision Oncology article titled, “Molecular Differences With Therapeutic Implications in Early-Onset Compared With Average-Onset Biliary Tract Cancers.”
At the time of this recording, our guest disclosures will be linked in the transcript.
Dr. Khorana, it's an absolute pleasure to have you here today, and welcome to the podcast.
Dr. Alok A. Khorana: Thank you. It's an absolute pleasure to be here and thank you for highlighting this article.
Dr. Rafeh Naqash: Absolutely. We're going to talk about science, obviously, and a few other things. So to start off, for the sake of our audience, which comprises academicians and community oncologists as well as trainees, can you tell us a little bit about biliary tract cancers, what we have learned over the last decade or so, where the standard of treatment currently lies. And then we can dive into the article that you published.
Dr. Alok A. Khorana: As many of you who treat GI cancers know, biliary tract cancers for a long period of time were sort of the orphan cancer in the GI cancer world. They're not nearly as common as, say, pancreatic cancer, and certainly not as common as colorectal cancer. They're sort of also, in this weird ‘no man's land’ between well known sort of adjuvant therapy trials in pancreatic cancer or colorectal cancer, but because they're not as high in volume, there weren't really large trials done in this population. What's really changed in the past decade, especially, has been the slow but sure realization that biliary tract cancers are in fact a target rich cancer, almost similar to what you would see with lung cancer, and that's only a slight exaggeration. And in some studies, as many as up to 40% of patients with biliary tract cancers can have something that's targetable. And that's really revolutionized the way we think of biliary tract cancers. It also separated this field from pancreatic cancer where formerly the two used to be lumped together, and even within biliary tract cancers, we are now slowly realizing that there are differences between intrahepatic, extrahepatic and gallbladder cancers. Big change is really afoot in this field, particularly with the identification of mutation directed targets.
Dr. Rafeh Naqash: Thank you for that explanation.
Now, another question I have is, although I don't see any GI cancers, but I have good colleagues of mine at our cancer center who see a lot of GI pancreatic/biliary cancers, and one of the things that comes up in our molecular tumor board often is how certain cancers of unknown primary end up being identified or categorized as biliary tract cancers based on NGS. And again, the uptake for these NGS is perhaps isn't optimal in the field yet, but in your practice, how do you approach situations like that? Do you use NGS in certain cases where the tissue of origin or the patterns of the mutations indicate that this might be biliary tract cancer and then treat the patient accordingly?
Dr. Alok A. Khorana: Yeah, that's true. And that's certainly how I approach things, and I would say even in my own personal practice, that has been a change. I was a little bit skeptical about the benefit of sort of tissue of origin type of testing in carcinoma of unknown, primarily, especially if you can sort of narrow it down to one or other area of the GI tract. But with the identification of sort of targeted subpopulations, especially of biliary tract cancer, I think it's become imperative. And I know we're going to get into the paper, but if you want to learn nothing else from this 20, 25 minute podcast, one lesson I just want to make sure everybody gets is that any patient with biliary tract cancer should have NGS done as soon as possible.
Dr. Rafeh Naqash: Thank you for highlighting that important aspect.
Now, going to the topic at hand, what was the driving factor? I've heard a lot about colorectal cancers, early onset versus later onset. What was the reason that you looked at biliary tract cancers? Is that something that you've seen on a rise as far as early onset biliary tract cancers is concerned?
Dr. Alok A. Khorana: Yeah. So we got into this subject also from starting out at colorectal cancer. And as you know, and I'm sure most of your audience knows, there's been a lot of literature out there over the past five, six, seven years suggesting and then documenting and then sort of proving and reproving that colorectal cancer is on the rise, and especially in people younger than age 50. And even in that population, it's on the rise in two different subpopulations, people in their 20s and 30s and then people in their 40s that are close to the screening colonoscopy rates. That's been investigated heavily. We still don't fully understand why that's happening, but it's not restricted to the United States. It's a worldwide phenomenon. You can see it in the United States, in North America. You can see it in western Europe, but you can also see it in many Asian countries with specific sort of subpopulations. For instance, in some countries, men are more likely to have early onset cancers.
And then a newer finding that sort of emerged over the past couple of years is that this early onset increase in cancers is not just restricted to colorectal cancer, although that's the one that sticks out the most, but in fact, is widespread across a bunch of different types of cancers. In my own research program, we had gotten into a sort of better understanding of early onset colorectal cancer a couple of years ago, driven primarily by the sort of patients that I saw in my practice. And it's just, as you know, when you have a couple of those heartbreaking cases and they're just impossible to forget, and it sort of just drives your attention, and then you want to do something to help them. And if you can't help them personally, then you want to do something that can change the field so that more of these patients are not coming in your clinic next year or the year after.
So a couple years ago, at the Cleveland Clinic where I practice, we created a center for young onset cancers, and at the time it was primarily focused on colorectal cancer. But as we are getting into colorectal cancer, we realize that beyond colorectal cancer, we are also starting to see more younger people with other cancers, including pancreas cancer, including gastric cancer, and including bile duct cancers. And we realized that because so much attention was being focused on colorectal, that maybe we should also be paying a little bit of attention to what was happening in this space. I want to, for your listeners, point out that the problem in bile duct cancers is not to the same degree as you see in colorectal cancer. Just a couple numbers to sort of, to set this in perspective: about 5%, 7% of bile duct cancers are young onset - it's not a huge proportion - 90%+ percent of patients are not young onset. But the impact on society, the impacts on those providing care, is obviously substantial for younger patients. And it is true that even though the proportion of patients is not that high, the incidence is rising.
And there's a very nice study done a couple of years ago and published that looked at what the cancers are that are rising at the highest rates. And bile duct cancer and gallbladder cancers were listed amongst the two with the highest rate, so about an 8% rate per year of increase. And so that's really what drove our interest was, as we're seeing early onset bile duct cancers, it's rising year by year, and what is this disease? Is it the same as you see in sort of the average patient with bile duct cancer? Is it different? How do we characterize it? How do we understand it? What are some of the causes precipitating it? And so that's what led us to sort of one of the investigations that we've documented in this paper.
Dr. Rafeh Naqash: Excellent.
So, talking about this paper, again, can you describe the kind of data that you use to understand the molecular differences and also look at potential immune signatures, etc., differences between the groups?
Dr. Alok A. Khorana: Yeah. So the objective in this paper was to look at genomic differences between early onset and usual onset, or average onset biliary tract cancers. And this sort of followed the paradigm that's already been established for early onset colorectal cancer, where you take a bunch of people with early onset disease, a bunch of patients with average onset or usual onset disease, and then look at the profiling of the tumors. And we've done this for genomics, we've done this for microbiomics, we've done it for metabolomics. And the lessons we've learned in colorectal cancer is that, in many ways, the profiles are actually quite substantially different. And you can almost think of them as diseases of the same organ, but caused by different processes, and therefore leading to different genotypes and phenotypes and microbiomes. We had absorbed that lesson from colorectal cancer, and we wanted to replicate it in this type of cancer.
But as we discussed earlier, this is a relatively rare cancer, not that many cases per year. For colorectal, we could do a single institution or two institution studies. But for this, we realized we needed to reach out to a source of data that would have access to large national data sets. We were happy to collaborate with Caris Life Sciences. Caris, many of you might know, is a provider of genomics data, like many other companies, and they house this data, and they had the age categorization of patients less than 50, more than 50. And so we collaborated with investigators at Caris to look at all the specimens that had come in of bile duct cancers, identified some that were young onset and some that were older onset. It was roughly about 450 patients with the early onset or young onset, and about 5000 patients with usual onset cases. And then we looked at the genomics profiling of these patients. We looked at NGS, whole exome sequencing, whole transcriptome sequencing, and some immunohistochemistry for usual, like PDL-1 and MSI High and things like that. And the purpose was to say, are there differences in molecular profiling of the younger patient versus the older patient? And the short answer is yes, we did find substantial differences, and very crucial for providers treating these patients is that we found a much higher prevalence of FGFR2 fusion. And that's important because, as I'm sure you've heard, there's a ton of new drugs coming out that are targeting specifically FGFR fusion in this and other populations. And hence my statement at the outset saying you’ve got to get NGS on everybody, because especially younger patients seem to have higher rates of some of these mutations.
Dr. Rafeh Naqash: Excellent. You also looked at the transcriptome, and from what I recollect, you identified that later onset tumors had perhaps more immune favorable tumor microenvironment than the early onset. But on the contrary, you did find that FGFR2 early onset had better survival. So how do you connect the two? Is there an FGFR link, or is there an immune signature link within the FGFR cohort for early onset that could explain the differences?
Dr. Alok A. Khorana: Yeah, that's a great question. So, to kind of summarize a couple of these things you talked about. So, one is we looked at these genomic alterations, and, yes, FGFR2 fusion was much more prevalent. It's close to 16% of young onset patients, as opposed to roughly 6% of average onset patients. So almost a threefold increase in FGFR fusion. And because there's so many drugs that are targeting FGFR fusion, and because the population included a period of time when these drugs had already been approved, we think some of the benefit or the improvement in median survival associated with being younger is likely driven by having more FGFR fusion and therefore having more drugs available to treat FGFR fusion related tract cancer with corresponding increase and increase in survival. And that was part of it.
There was one other alteration, NIPBL fusion, that's been sort of known to be associated with a certain subtype of cholangiocarcinoma, but it doesn't really have a drug that targets it, so it's not sort of very useful from a clinical perspective.
The other two things you talked about, so transcriptome and immuno oncology markers, we found a couple different results on this. So one is that we found in younger people, angiogenesis was enriched, and why this is so we don't quite have a good answer for that. The other was inflammatory responses. So there's a couple of gamma interferon pathways and a couple other types of pathways that you can sort of do pathway analysis, and we found that those were enriched in the older patients or the average onset patients. But the benefit for immunotherapy was similar across the two groups. So even though we saw these differences in signaling in terms of which pathways are upregulated or downregulated, it didn't seem to translate into the current generation of immune checkpoint inhibitors that we're using in terms of benefit for patients. But we did see those differences.
Dr. Rafeh Naqash: I completely agree, Doctor Khorana. As you mentioned, that one size fits all approach does not necessarily work towards a better, optimal, personalized treatment stratification. So, as we do more and more sequencing and testing for individuals, whether it's early onset cancers or later onset cancers, figuring out what is enriched and which subtype, I think, makes the most sense.
Now, going to the FGFR2 story, as you and most listeners probably already know, FGFR is an approved target, and there are a band of FGFR inhibitors, and there's some interest towards developing specific FGFR2, 3 fusion inhibitors. What has your experience with FGFR inhibitors in the clinic been so far? And what are you personally excited about from an FGFR standpoint, in the drug development space for GI cancers?
Dr. Alok A. Khorana: Yeah, I think the whole FGFR fusion story sort of actually deserves more excitement than it's gotten, and it may be because, as I mentioned earlier, biliary tract cancers are a relatively low volume type of cancer. But the results that we are seeing in the clinic are very impressive. And the results that we are anticipating, based on some ongoing phase two and phase three trials, appear to be even more impressive for the very specific inhibitors that are about to hopefully come out soon.
Also, the possibility of using successive lines of FGFR inhibitors - if one fails, you try a second one; if the second one fails, you try a third one because the mechanisms are subtly different - I think it will take a little while to figure out the exact sequencing and also the sort of the rates of response in people who might previously have been exposed to an FGFR inhibitor. So that data may not be readily available, because right now most patients are going in for longer trials. But having that type of possibility, I think, kind of reminds me of the excitement around CML back when imatinib suddenly became not the only drug and a bunch of other drugs came out, and it's kind of like that. I think again, it's not a very common cancer, but it's really wonderful to see so many options and more options along the way for our patients.
Dr. Rafeh Naqash: Thank you. Now, going to your personal story, which is the second part of this conversation, which I think personally, for me, is always very exciting when I try to ask people about their personal journeys. For the sake of the listeners, I can say that when I was a trainee, I used to hear about Dr. Khorana’s course, I always thought that Dr. Alok Khorana was a hematologist. My friends corrected me a few years back and said that you’re a GI oncologist. Can you tell us about your love for GI oncology and the intersection with hematology thrombosis, which you have had a successful career in also? Can you explain how that came about a little bit?
Dr. Alok A. Khorana: Yeah, sure. So it is a common, I guess I shouldn't say misperception, but it's certainly a common perception that I'm a hematologist. But I'll sort of state for the record that I never boarded in hematology. I did do a combined hem-onc fellowship, but only boarded in oncology. So I'm actually not even boarded in hematology. My interest in thrombosis came about- it's one of those things that sort of happen when you're starting out in your career, and things align together in ways that you don't sort of fully understand at the time. And then suddenly, 10 years later, you have sort of a career in this.
But it actually came about because of the intersection of, at the time, angiogenesis and coagulation. And this is the late ‘90s, early two ‘00s, there was a lot of buzz around the fact that many of the factors that are important for coagulation are also pro angiogenic and many factors that are coagulation inhibitors. These are naturally occurring molecules in your body, and can be anticoagulant and anti angiogenic. A great example of this is tissue factor, which is, as you'll remember from the coagulation pathways, the number one molecule that starts off the whole process. But less widely appreciated is the fact that nearly every malignancy expresses tissue factor on its cell surface. This includes breast cancer, it includes leukemia cells, it includes pancreatic cancer. In some cancers, like pancreatic cancer, we've even shown that you can detect it in the blood circulation. And so for me, as a GI oncologist who was seeing a lot of patients get blood clots, it was particularly fascinating to sort of see this intersection and try and understand what is this interaction between the coagulation and angiogenic cascades that's so vital for cancers. Why is coagulation always upregulated in cancer patients? Not all of them get blood clots, but subclinical activation of coagulation always exists. So I would say I was fascinated by it as an intellectual question and really approached it from an oncology perspective and not a hematology perspective.
But then as I got deeper into it, I realized not everybody's getting blood clots, and how can I better predict which patients will get blood clots. And so I had both a hematology mentor, Charlie Francis, and an oncology mentor, Gary Lyman. And using sort of both their expertise, I drafted a K23 career development award specifically to identify predictors of blood clots in cancer patients. And that's the multivariate model that later became known as the Khorana Score. So again, I approach it from an oncology perspective, not a hematology perspective, but really a fascinating and still, I would say an understudied subject is why are cancer patients having so many clotting problems? And what does it say about the way cancer develops biologically that requires activation of the coagulation system across all of these different cancers? And I think we still don't fully understand the breadth of that.
Dr. Rafeh Naqash: Very intriguing how you connected two and two and made it a unique success story. And I completely agree with you on the tissue factor. Now there's ADCs antibody drug conjugates that target tissue factor, both a prude as well as upcoming.
Now, the second part of my question is on your personal journey, and I know you've talked about it on social media previously, at least I've seen it on social media, about your interactions with your uncle, Dr. Har Gobind Khorana, who was a Nobel Prize winner in medicine and physiology for his work on DNA. Could you tell us about how that perhaps shaped some of your personal journey and then how you continued, and then also some personal advice for junior faculty trainees as they proceed towards a successful career of their own?
Dr. Alok A. Khorana: Yeah, thank you for bringing that up. So very briefly, this is about my uncle. He's actually my great uncle. So he's my grandfather's youngest brother. And I grew up in India in the ‘70s and ‘80s, and at the time, I ran away from this association as fast as I could, because growing up in India in the 70s and ‘80s, it was a socialist economy. There wasn't a lot going on. There was certainly none of the IT industry and all of everything that you see right now. And so there were very few icons, and my great uncle was definitely one of those few icons. As soon as you mentioned your last name, that would sort of be the first question people would ask. But he did serve as a role model, I think, both to my father, who was also a physician scientist and a professor of medicine, and then to myself in sort of making me realize, one, that you can't really separate medicine from science. I think those are really integrated, and we want to ask questions and answer questions in a scientific manner. He chose to do it in a basic science world. My father did it in a clinical science world, and I have done it in a clinical and a translational science world. Again, sort of using science as the underpinning for sort of understanding diseases, I think, is key. And so that was certainly a massive inspiration to me.
And then after I immigrated to the US in the late ‘90s, I met him on a regular basis. He was certainly very inspirational in his successes, and I realized the breadth of what he had done, which I did not realize in my youth growing up. But this is a person who came to the US. This was before Asian immigration was even legal. So he got here and they had to pass a special bill in Congress to let him be a citizen that was based on the sort of work that he had done in Canada and in the UK before he came here. And then he sets up shop in the University of Wisconsin in Madison and hires tons of these postdocs and essentially converted his lab into this massive factory, trying to figure out the genetic code. Really just the type of dedication that that needs and the amount of work that that needs and the ability to do that in a setting far removed from where he grew up, I think it's just really quite mind boggling.
And then he didn't stop there. He got the Nobel for that, but I have these letters that he wrote after he got the Nobel Prize, and he was just completely obsessed with the possibility that getting the Nobel would make him sort of lose his mojo and he wouldn't be as focused on the next aspects of science. And he was just really dedicated to synthesizing DNA in the lab, so creating artificial DNA, which he ended up doing. And the offshoot of that work, so not just the genetic code, but PCR essentially was developed by his lab before it became sort of what we now know as PCR. And then ditches all of that in the ‘80s and ‘90s and moves to understanding the retina and just focuses on retinal disorders. And then signal transduction, essentially trying to figure out when a single photon of light hits your eye, what happens biologically. It's a completely different field. And just took that on and spent the next 20,30 years of his life doing that. So the ability to sort of change fields, I thought that was very inspirational as well, that you don't have to just stick to one question. You can get into one question, answer it as much as possible, and then find something else that's really interesting to you and that really grabs your attention, and then stick with that for the next couple of decades. So lots to learn there.
Dr. Rafeh Naqash: Thank you. Thank you. And then, based on some of your personal lessons, what's your advice for junior faculty and trainees as you've progressed in your career?
Dr. Alok A. Khorana: I think, number one, and I can't emphasize this enough, and sometimes it actually causes a little bit of anxiety, but it is finding the right mentor. And for me, certainly that was key, because my mentor, who was Charlie Francis, was not an oncologist who was a hematologist, but was like me, sort of supported this idea of trying to understand, hey, why does coagulation interact with cancer? And so he approached it from a hematology perspective, I approached it from a cancer perspective, but he sort of gave me the freedom to ask those questions in his lab and then later on in the clinical setting and clinical translational setting, and then got me access to other people who are experts in the field and introducing you and then getting you on committees and making sure you sort of get into clinical trials and so on. And so having a mentor who sort of supports you but doesn't stifle you, and that's really key because you don't want to just ask the question that the mentor is interested in. And as a mentor now, I don't want to have my mentee ask the question that I'm interested in, but also a question that the mentee is interested in. And so there's a little bit of a chemistry there that's not always replicable, and it can go wrong in sort of five different ways, but when it goes right, it's really vital. And I mentioned it causes anxiety because, of course, not every day is great with your mentor or with your mentee, but over a period of time, has this person done sort of their best to get your career off to a start? And have you served that mentor well by doing the things that are– there's responsibilities on both sides, on both on the mentor and on the mentee. And if you can find that relationship where there's a little bit of chemistry there and both of you are effectively discharging both your responsibilities and satisfying your intellectual curiosity, I think that can't be beat, honestly. To me, sort of number one is that and everything else follows from that. So, the networking, making sure your time is sort of allocated appropriately, fighting with sort of the higher ups to make sure that you're not having to do too much, things that are sort of away from your research interests, all of that sort of flows from having the right person.
Dr. Rafeh Naqash: Couldn't agree with you more, Dr. Khorana, thank you so much. It was an absolute pleasure. Thank you for sharing with us the science, the personal as well as the professional journey that you had. And hopefully, when you have the next Khorana Score, Khorana score 2.0, JCO Precision Oncology will become the home for that paper and we'll try to have you again maybe in the near future.
Thank you for listening to JCO Precision Oncology Conversations. Don't forget to give us a rating or review and be sure to subscribe so you never miss an episode. You can find all ASCO shows at asco.org/podcast. Thank you so much.
The purpose of this podcast is to educate and to inform. This is not a substitute for professional medical care and is not intended for use in the diagnosis or treatment of individual conditions.
Guests on this podcast express their own opinions, experience and conclusions. Guest statements on the podcast do not express the opinions of ASCO. The mention of any product, service, organization, activity or therapy should not be construed as an ASCO endorsement.
Disclosures:
Dr. Khorana - Honoraria Company: Pfizer, Bayer, Anthos, Sanofi, BMS, WebMD/MedscapeConsulting or Advisory Role Company: Janssen, Bayer, Anthos, Pfizer, Sanofi, BMS Research Funding Company: Anthos, Bristol-Myers, Squibb Travel, Accommodations, Expenses Company: Janssen, Bayer, Bristol-Myers Squibb
In this JCO Precision Oncology Article Insights episode, Miki Horiguchi summarizes an editorial: “Expanding the Reach of Personalized Medicine in Cancer Care: Current Progress and Future Directions of JCO Precision Oncology” by Dr. Yushu Shi et al. published on May 30, 2024.
TRANSCRIPT
Hello and welcome to JCO Precision Oncology Article Insights. I’m your host Miki Horiguchi, an ASCO Journals Editorial Fellow. Today, I will be providing a summary of the article titled “Expanding the Reach of Personalized Medicine in Cancer Care: Current Progress and Future Directions of JCO Precision Oncology”. This is an editorial by Dr. Yushu Shi and colleagues that investigated trends in publication, peer review, and global influence of JCO precision oncology.
Before getting into the editorial, I would like to briefly introduce to precision oncology and the JCO Precision Oncology journal as a leading platform for research in this field.
Precision oncology is a personalized medicine approach that leverages advances in genomics and molecular profiling of tumors, biomarker-driven decisions, and targeted therapies to enhance clinical care for patients with various cancer types. Since there are many aspects to consider, such as biologic, clinical, and statistical aspects, advances in precision oncology also come with numerous challenges. These include identifying targetable mutations and addressing tumor heterogeneity and drug resistance. Other challenges are developing new study designs and statistical analysis methods to evaluate new approaches, as well as developing methods to manage large and complex datasets.
Since the American Society of Clinical Oncology introduced the journal JCO Precision Oncology (or JCO PO) in 2016, it has played an important role as a dedicated platform for publishing high-quality research and promoting discussions on those challenges.
JCO PO is a peer-reviewed, online-only, article-based journal publishing articles across multiple categories. These include original reports, case reports, review articles, commentaries, correspondence, editorials, special articles, and molecular tumor board case discussions.
The journal’s contribution to the advancement of the field is reflected in the journals’ impact factor, which was 4.6 in 2022 and 5.3 in 2023.
In the editorial, Dr. Shi and colleagues first investigated the publication trends from 2017 to 2022, highlighting cancer types, article types, the number of citations, and topics of papers published in JCO PO that have had broad impact. The papers accepted at JCO PO covered a broad range of research topics, including genomics-driven tumor treatments, molecularly selected targeted therapy, translational oncology, cancer biomarkers, gene expression and profiling, biostatistics and clinical trial methodology, epidemiology, and cancer prevention and control. The most common cancer types are thoracic, GI, and breast cancers. Original reports were more likely to be cited than case reports. The average number of annual citations for original reports was 4.33, while it was 1.39 for case reports. The authors listed the 10 most cited papers published in JCO PO in a table. The most cited paper was an original report titled “Landscape of Microsatellite Instability Across 39 Cancer Types” by Bonneville and colleagues. The paper has been cited more than 600 times since it was published in 2017.
Next, the authors conducted an analysis to see trends in peer-review. When manuscripts are submitted to JCO PO, they go through a rigorous peer-review process. Reviewers evaluate them based on five key metrics: importance of the study, originality, quality of writing, relevance to clinical practice, and scientific strength. Each metric is rated on a scale from 1 to 5, with higher scores indicating better performance. Dr. Shi and colleagues compared the rating scores between accepted and rejected manuscripts of original reports and case reports. They found that the median score of accepted manuscripts was above 3.5 for all metrics. The findings highlight that no single metric determines acceptance, underscoring the importance of excelling in all five areas when developing manuscripts.
Finally, the authors looked at trends in global influence in JCO PO. Counting the country where the corresponding author’s institution is located, Dr. Shi and colleagues found that JCO PO has accepted manuscripts from 36 countries, indicating a steady increase in its global reach. The United States accounts for about 71% of the total contributors. The other top contributors include France, Canada, Italy, Australia, the Netherlands, Germany, Japan, the United Kingdom and China. Notably, global collaborations among authors have significantly increased, with the proportion of papers from multiple countries more than doubling from 12.5% in 2016 to 26.5% in 2022. These facts reflect JCO PO’s ongoing commitment to engaging with the international precision oncology community and encouraging global research submissions.
At the end of the editorial, the authors provided some guidance for future authors. Across original reports and case reports, successful submissions to JCO PO typically have a translational focus. They provided a mechanistic understanding of tumor biology and utilized cancer genomics to inform clinical decision making. The authors also highlighted several underrepresented but growing areas of interest at JCO PO. These include pediatric oncology, sarcomas, ethics, trial methodology, informatics, computational approaches, and statistical methods related to precision oncology. Furthermore, the increasing significance of germline genetics, pharmacogenetics, molecular diagnostics, and molecular epidemiology in precision oncology has been recognized and valued by JCO PO.
JCO PO also has special series issues. The special series feature timely research topics, such as Equity in Precision Medicine, Statistical Methods for Precision Oncology, and Next Generation Sequencing. Through these special series, JCO PO continues to lead the advancement of the application of precision oncology across a diverse patient population.
The authors also provided points to consider when submitting case reports. For successful case report submissions, especially n-of-1 reports that showcase novel findings with potential clinical impact, it is crucial to include robust data to support the clinical observations, investigate underlying mechanisms, and ensure proper protection of patients’ identity and autonomy. An n-of-1 report alone is often insufficient for publication. Successful case reports typically extend beyond a single patient, examining the phenomenon in multiple patients and providing mechanistic validation, either in vitro or through preclinical models.
Thank you for listening to JCO Precision Oncology Article Insights and please tune in for the next topic. Don’t forget to give us a rating or review and be sure to subscribe, so you never miss an episode. You can find all ASCO shows at asco.org/podcasts.
JCO PO author Dr. Jonathan D. Tward, M.D., Ph.D., FASTRO, at the HCI Genitourinary Cancers Center and the Huntsman Cancer Institute at the University of Utah, shares insights into his JCO PO article, “Using the Cell-Cycle Risk Score to Predict the Benefit of Androgen-Deprivation Therapy Added to Radiation Therapy in Patients With Newly Diagnosed Prostate Cancer.” Host Dr. Rafeh Naqash and Dr. Tward discuss how the cell-cycle risk score predicts the benefit of androgen-deprivation therapy in prostate cancer treatment.
TRANSCRIPT
Dr. Abdul Rafeh Naqash: Hello and welcome to JCO Precision Oncology Conversations, where we bring you engaging conversations with authors of clinically relevant and highly significant JCO PO articles. I'm your host, Dr. Rafeh Naqash, Assistant Professor at the OU Health Stephenson Cancer center. Today, we are excited to be joined by Dr. Jonathan Tward, Leader at the HCI Genitourinary Cancer Center, and Vincent P. and Janet Mancini Presidential Endowed Chair in Genitourinary malignancies at the Huntsman Cancer Institute at the University of Utah. Dr. Tward is also the lead author of the JCO Precision Oncology article titled “Using the Cell-Cycle Risk Score to Predict the Benefit of Androgen-Deprivation Therapy Added to Radiation Therapy in Patients With Newly Diagnosed Prostate Cancer.”
At the time of this recording, our guest's disclosures will be linked in the transcript.
Doctor Tward, welcome to the podcast and thank you for joining us today.
Dr. Jonathan Tward: Thank you so much, Dr. Naqash. I'm excited to share this important research with your audience.
Dr. Abdul Rafeh Naqash: Awesome. For the sake of simplicity, we'll refer to each other using our first names, if that's okay with you.
Dr. Jonathan Tward: That's great.
Dr. Abdul Rafeh Naqash: Okay. So, Jonathan, this complex but very interesting topic revolves around a lot of different subtopics as I understand it. There is genomics, there are implications for treatment, there is machine learning and computational data science research. So, to start off why you started this project or why you did this research, could you, for the sake of our audience, try to help us understand what androgen deprivation therapy is? When is it used in prostate cancer? When is it used in combination with radiation therapy? And that would probably give us a decent background of why you were trying to do what you actually did in this research.
Dr. Jonathan Tward: Yes, thank you very much. So, men who are diagnosed with localized prostate cancer, which is the majority of prostate cancer diagnosis, are faced with a lot of treatment decisions. And those decisions range all the way from, “Should I just go on active surveillance with the idea that it might be safe to treat later?” to “Should I consider surgery or radiation?” And then there's various forms of radiation. Now, as a radiation oncologist, one of the things that I have to consider when I meet a patient with localized prostate cancer who is pondering receiving radiation therapy, is whether or not we want to intensify treatment by doing more than just radiation alone. And androgen deprivation therapy, very specifically also thought of as chemical castration, what that really is is some kind of therapy where you are trying to reduce a man's testosterone levels to nearly zero. And the rationale for using androgen deprivation therapy in prostate cancer and in this case, specifically localized prostate cancer, is that one can think of testosterone almost as the food and growth signal for prostate cancer. There have been numerous prospective randomized trials that have been performed in the past that have clearly demonstrated that adding androgen deprivation therapy to certain contexts of patients with localized prostate cancer receiving radiation improves the outcome, including risk of metastasis and overall survival.
The problem is, we don't want to just intensify therapy for everybody who walks through our doors with localized prostate cancer. Some men have lower risk disease, and some men have higher risk disease. And conventionally, the way we make this decision is by looking at things like NCCN risk groups, which kind of lump patients into a few different boxes, generally speaking, called low risk, intermediate risk, and high risk. And if you think of those risk groups, the patients with the contemporary standard of who to add ADT to are men who are considered high risk localized, or men who are considered unfavorable intermediate risk localized. That being said, I think there's a recognition that we're overtreating some unfavorable intermediate risk men and undertreating them, and the same could be said of high-risk disease. So, I think we're always looking for better tools that make it a little bit more personalized, rather than lumping men into just one of several boxes.
Dr. Abdul Rafeh Naqash: Sure. And this sort of reminds me of the oncotype DX, in a way, trying to connect people with ER/PR, breast cancer, and where chemotherapy, plus anti-estrogen and progesterone therapy may be applicable. So, I think you were trying to do something similar in this research, and as far as I remember, please correct me if I'm wrong, this is knowledge that I remember from my board exams, we classify this high risk, intermediate risk, and low risk based on the Gleason score. Is that correct? Is that still true, or has this changed?
Dr. Jonathan Tward: It's still true. Conventional risk stratification, which is still used, literally only looks at a few parameters. You mentioned one, which is the Gleason score, which is really a human subjective judgment by a pathologist about how deranged cells look under a microscope. That's one parameter. The second parameter is the PSA value at the time of diagnosis. And the third parameter is the cT stage, which is really based on the digital rectal exam. Now, when you ponder that the entirety of our risk classification system is based on two subjective and one objective pieces of information, meaning what a Gleason score looks like, what the T stage is based on human interpretation, and then the only objective piece of data, PSA, it's rather rudimentary way of classifying men. I mean, it's done us well since the late ‘90s, when that particular classification system was derived. But it strikes me as odd that we should take all newly diagnosed localized prostate cancer patients and say you fit into one of three boxes, when we know there's so much more complexity to people and so many different treatment options and choices out there, which we're trying to match to the patient to ensure that we right size the treatment for them.
Dr. Abdul Rafeh Naqash: Understood. Now, as we go into the precision medicine component of this research, there's genomics research in metastatic cancers. But is there any genomics research in early-stage prostate cancer where there have been differences that have been identified between the intermediate low risk, high risk? Is that something that has been explored to date?
Dr. Jonathan Tward: Well, there are certainly somatic mutations that track with certain aggressive features. But I think when I think about the spirit of your question, within the localized prostate cancer space, there's been several molecular signatures that have been developed and, in fact, been commercialized that have been shown quite clearly that if you have a certain array of gene expressions, let's say, that that can correlate with metastasis or risk of recurrence or death. And the work that we're talking about today is one that actually uses one of the commercially available biomarkers, commercially it's known as Prolaris. But very specifically, in the work that I think we're discussing today, what we're looking at is cell cycle progression genes. And these are genes that maybe, to simplify it, are sort of hallmarks of how quickly cells are turning over. And what's interesting about looking at cell cycle progression is it's not certainly particular to prostate cancer. I mean, you could make an argument that cell cycle progression genes are probably relevant measures in any cancers, but there's been much work done over the past 15 to 20 years that have clearly validated that this particular cell cycle progression gene signature, which is now commercially available, clearly correlates with risk of progression, risk of metastasis in localized prostate cancer patients, whether they're receiving surgery or radiation. But what we've done is we've built upon this molecular work and added clinical risk features and added results of prospective randomized trials to use this test to personalize the precise risk reduction of what would happen to a man who is pondering adding ADT to radiation therapy. So, it's a very powerful precision tool.
Dr. Abdul Rafeh Naqash: Sounds very interesting. When you go deeper into this platform, is this genomic testing platform, does it incorporate RNA transcriptome or is it DNA, or is it a composite of both?
Dr. Jonathan Tward: There are various molecular tests that are out there. In this particular case, these are mRNA expression levels of cell cycle progression genes, and they are kind of calibrated against some normal housekeeping genes, which is how the test is run.
Dr. Abdul Rafeh Naqash: Understood. So, from what I understand in the discussion, you very appropriately said, in fact in your first paragraph, the goal here is to match patient level precision medicine approaches and reconcile them with population level therapeutic options. It's a very catchy statement. Can you help explain for our audience how you tried to do that? And this goes back to the question that you were trying to understand, where to use combination therapy in a localized prostate cancer based on risk stratification and deriving that risk stratification from the cell cycle score and then arriving to certain thresholds. So could you go through that in simple terms to help us understand how you tried to do it and what was the outcome and what are the implications of that?
Dr. Jonathan Tward: Sure, there's a lot to unpack there, but I'll do my best to simplify it. So, we'll start with the basic question that faces a patient and their radiation oncologist, which is, if they're going to receive radiation, should you add hormone therapy? And if hormone therapy was completely nontoxic, you'd say, “Sure, just add it to everybody if there's a benefit.” But the problem is, of course, hormone therapy is associated with all kinds of unpleasant side effects and additional risks, so we don't want to utilize it unless we're sure that the benefit is clear. When you think about the way most of oncology decides whether or not adding an intervention should be done in a particular patient context, it's actually been derived originally from prospectively randomized trials, which usually assigned a hazard ratio or some kind of known relative reduction to doing ‘thing B’ versus ‘thing A’ or ‘thing B’ in addition to ‘thing A’.
But what's curious about always looking at hazard ratios and saying that those are the reasons why you should do additional things, discounts a really important fact, which is the baseline risk of something bad happening has to be accounted for first before you decide whether or not it a relative risk reduction matters. So to state more clearly, if I knew a prostate cancer patient sitting in front of me only had a 2% risk of developing metastasis within 10 years, if I just did radiation alone, if I then say adding hormone therapy might cut that in half from 2% to 1%, a patient might say, “You know what? I'm not sure I want to accept the toxicity of many months of hormone therapy to cut my risk of metastasis from 2% to 1%.” But if you had a patient where that risk was 20% risk of metastasis with radiation alone, and you told them I can cut that risk down to 10% or 12%, then that's something they would seriously consider.
And so what this work really does is precisely that. It gives us a tool where, using the molecular signature of the cell cycle progression genes, which afford a patient a certain risk of metastasis, and also taking into account clinical risk factors that we know are prognostic, Gleason score, PSA, their age, how many cores of the biopsy were possible. We use all this information, and I'll use a strange term, multiplex it into a robust risk model that will prognosticate extremely clearly what that patient's precise risk of metastasis will be within the next 10 years, and this is the key point, if they receive radiation alone.
So, think of this work in two phases. Phase one is calibrate the risk in a patient if they get radiation alone, by using both molecular and clinical prognosticators. But then take the power of numerous randomized trials, which have clearly set the hazard ratio reduction for adding the hormone therapy, and then using mathematical principles, applying that hazard ratio risk reduction to the absolute risk. And then what you ultimately do is, at a very individual level, have a patient sitting in front of you where you can say, “Mr. Jones, I've run this test on you, and I can tell you definitively that if you receive radiation therapy for your localized prostate cancer, the risk of metastasis will be 12%. But if you add, let's say, six months of hormone therapy, that could be reduced to 7%, and the absolute risk reduction might only be 5%.” And if you think about that number in a number needed to treat mentality, then you could say, “Listen, I have to give 20 men identical to you, hormone therapy for one to benefit. Is that worth it to you?”
And what it really does is it empowers the patient. Rather than following a guideline that says, “Effectively, thou shalt do this for this risk group,” you really want to engage the patient in the conversation about the risk benefit of what you're going to do. And I think it's uncommon in oncology for physicians to be able to very precisely tell a patient sitting in front of them, if you do ‘thing A’, this is the risk, something bad happen. If you do ‘thing B’, this is how the risk reduces. And I think now we really get into shared decision making, rather than a, “Trust me, I'm a doctor,” paternalistic situation.
Dr. Abdul Rafeh Naqash: That's a very interesting approach. Again, you're basically personalizing the personalized medicine approach, refining it further, and involving the patient in discussions, which helps them understand why something would make sense. And some of this, as you might already know, people have tried to do in some other tumor types, hasn't necessarily led to significant clinical decision-making changes. But I think the way the field is evolving, especially this research that you published on and others are working towards, will hopefully result in more personalized approaches for individual decision making for these patients.
Now, I do understand that simplicity sometimes results in more uptake of some information versus when sometimes things get more complex. So, in your assessment, when you came up with these results, you looked at the genomic score, you took the randomized clinical trial data, you did the absolute risk reduction. From what I understood in the manuscript, it does look like you did come up with a threshold of what would appropriately risk stratify individuals, meaning individuals that are at a higher risk if they cross that threshold, versus individuals that are at a lower risk if they cross that threshold. Is that a fair statement or is this a continuum? So there is no binary, but this is over a scale that this assessment can be made.
Dr. Jonathan Tward: So, there are elements of your summary that are fair, but this is a continuum which allows any individual to accept whatever risk reduction they want. That being said, there is no standard in oncology for what percent risk should you intensify a treatment for? And when you poll physicians and doctors as to how much reduction in death or how much reduction in metastasis, doctors and patients are all over the map at what they consider to be a threshold. But we designed these thresholds actually from prior work, based on surveying both patients themselves, as well as experts who were on cooperative trial group steering committees, and ask them, essentially, “At what level of risk reduction would you want to intensify treatment?” And what's interesting is most people who are asked that question are willing to do more treatment intensity for an important outcome like metastasis if the absolute risk reduction of that event happening is 5%. So as a general principle, that's how it was set.
These thresholds in the current paper we're discussing actually weren't defined in this current work. They were defined in prior works, where we had clearly shown in retrospective data sets that they could discriminate very well who does or doesn't benefit from hormone therapy. What's, I think, novel about this paper, even though we had previously validated those thresholds, is that now that we're using the randomized trial data, it's extremely robust in our risk estimates, and we can say that it's truly a predictive biomarker. Because it's one thing to prognosticate an outcome, but predict a difference in treatment A versus treatment B usually requires randomized trial data so that you get the highest level of evidence and the confidence that it works.
Dr. Abdul Rafeh Naqash: So the next steps for this very, very provocative research, is it something prospective validation or are you going to try to utilize maybe proper group trial data or other pharma trial data, individual patient data to risk stratify these individuals and validate?
Dr. Jonathan Tward: So these thresholds, for example, that you refer to are very well validated. There's multiple prior studies, well over at this point, 1500 patients where there's validation. And yes, we have reached out to cooperative groups to do some additional validation. That being said, this work is already ready for prime time and being used. In fact, this test is the commercially available Prolaris test. The results gleaned from this work are published on the score report that a patient and a physician receives. So the reality is that this is already existing as a clinical tool in the community. And the NCCN guidelines also support the use of this and other tests to move from a stratification to personalized medicine. So it's not like this is so much in the experimental realm as it is effectively a complete tool that is being used today. And effectively, it's available for any patient or physician diagnosed with localized prostate cancer to immediately order on biopsy tissue.
Dr. Abdul Rafeh Naqash: One naive question, Jonathan, I wanted to ask is most prostate cancers tend to be prostatic adenocarcinoma. So if it's a neuroendocrine localized prostate cancer, does the same risk assessment apply? Because neuroendocrine tumors in general seem to be higher replication stress or higher tendency to metastasis. Does it change from your perspective, from the genomic assessment standpoint, the CCR score standpoint?
Dr. Jonathan Tward: That's a very interesting question, because what I will tell you is that there are probably a lot of, well, I wouldn't say a lot, but there are some neuroendocrine cancers mixed in with the adenocarcinomas that no one identified as neuroendocrine, which in a way were baked into the cake of the risk signature. Even though that is so, I dont think we’ve independently looked very specifically at known neuroendocrine cancers and compared them to the adenocarcinomas. What I would actually argue though, is that if you have a neuroendocrine cancer sitting in front of you, the point about whether or not you're adding ADT is relatively moot because neuroendocrine cancers may or may not respond to ADT, and you have to start considering chemotherapeutic-like decisions.
So the question, which is very interesting and academic, is that I would presume the cell cycle progression score should be elevated, although I don't know that in a neuroendocrine cancer, this tool doesn't appear to be useful at this moment for neuroendocrine cancers because we're not making decisions about chemo. That's an interesting and provocative question, and now you make me want to study that. So potentially, the next paper would be neuroendocrine cancers, whether or not it might prognosticate using a topicide or something else like this. But we would have to rely on prospective trial data as well to see whether or not we could use it the same way.
Dr. Abdul Rafeh Naqash: Hopefully, if you do work on it, then you can submit the manuscript again to JCO PO for us to talk again.
Dr. Jonathan Tward: Yeah, and you'll be on the author bar.
Dr. Abdul Rafeh Naqash: Appreciate the inclusion. So thank you so much, Jonathan, for talking to us about the science. And a few quick minutes about yourself. Can you tell us a little bit about your career trajectory, how you ended up doing what you're doing, and maybe some lessons learned and some advice for early career junior investigators that would be helpful for them?
Dr. Jonathan Tward: Yes, that's a happy memory. When I was a young undergrad, I was fortunate to do some volunteer work in a radiation oncology department and had mentors there who guided me into considering a career in medicine and specifically a career as a physician scientist. So I'll start with the best advice is to get mentors early on and throughout your career who are really interested in your career development and who are accomplished that can kind of help you along. But I went to medical school with an open mind and continued to love oncology. I think it has some of the most complex questions that are unanswered. It is very high stakes oncology. There's still a lot of death and disability and consequences of our therapies. And I just love the idea of working in an environment, both clinically and as a researcher, to try to solve some of those questions like, how do I improve outcomes? How do I make therapy less toxic?
And radiation oncology for me, was a nice fit in genitourinary cancer, I guess, specifically because mid GU cancer realm patients are presented with a menu of treatment options. It's kind of interesting. It's a little bit unlike other cancers. But I had fantastic mentors throughout both my medical school as well as residency program who really helped guide me and encourage me along the way. And so without spending too much time, I would say go out of your way to find people who are successful at what they do, are interested in making you better, and really sit at their knee and listen to them when they are trying to guide you because they really have your best interests in mind. And I think as a mentor and a mentee, what makes me most proud is watching people I've trained go out and succeed. I mean, the reward of being a mentor is watching your mentees succeed.
Dr. Abdul Rafeh Naqash: Thank you. Appreciate all those words of wisdom, Jonathan, and excited to see all the subsequent steps and results from the research that you're doing. Thank you again for joining us today and providing a very simple summary of a very complex topic which I think our audience and perhaps some of the trainees listening to this podcast will appreciate. We really appreciate your time.
Dr. Jonathan Tward: Thank you so much, Rafeh.
Dr. Abdul Rafeh Naqash: And thank you for listening to JCO Precision Oncology Conversations. Don't forget to give us a rating or review and be sure to subscribe so you never miss an episode. You can find all ASCO shows at asco.org/podcast.
The purpose of this podcast is to educate and to inform. This is not a substitute for professional medical care and is not intended for use in the diagnosis or treatment of individual conditions.
Guests on this podcast express their own opinions, experience, and conclusions. Guest statements on the podcast do not express the opinions of ASCO. The mention of any product, service, organization, activity or therapy should not be construed as an ASCO endorsement.
Dr. Tward Diclosures:
HonorariaCompany name: Bayer
Consulting or Advisory RoleCompany name: Myriad Genetics, Blue Earth Diagnostics, Janssen Scientific Affairs, Merck, Bayer, Boston Scientific, Myovant Sciences, Myriad Genetics, Lantheus Medical Imaging
Research FundingCompany name: Bayer, Myriad Genetics
Travel, Accommodations, ExpensesCompany name: Myriad Genetics, Bayer
In this JCO Precision Oncology Article Insights episode, Miki Horiguchi summarizes two articles: “Biomarker-Driven Oncology Trial Design and Subgroup Characterization: Challenges and Potential Solutions” by Wang, et al. published on June 7, 2024, and “Biomarkers in Oncology: Complexities in Biomarker-Driven Studies and Statistical Analysis” by Uno, et al. published on July 22, 2024.
TRANSCRIPT
Miki Horiguchi: Hello and welcome to JCO Precision Oncology Article Insights. I'm your host, Miki Horiguchi, an ASCO Journal Editorial Fellow. Today, I'll be providing summaries for two articles.
The first article is a review article titled, “Biomarker-Driven Oncology Trial Design and Subgroup Characterization: Challenges and Potential Solutions,” by Dr. Jian Wang and colleagues. Biomarker driven clinical trials represent a key component of precision medicine, focusing on tailoring treatments to patients based on specific biomarkers. By identifying and targeting therapies to patients who are most likely to benefit, these trials aim to improve treatment outcomes and reduce adverse events.
The article highlights several important points to optimize biomarker driven clinical trials. The authors first reviewed US FDA approvals in biomarker defined subgroups and conducted an in-depth analysis of key regulatory considerations. They developed an innovative decision tree to guide designing biomarker based clinical trials. In addition, they clarified the statistical challenges, including ones found in the all-comers study design. The authors found that most of the US FDA approvals are being restricted to the biomarker positive subgroup, indicating that observed treatment benefits in the overall population are heavily influenced by the biomarker positive patients. This raises concerns as the treatment effect in the biomarker negative subgroup may be smaller but still clinically meaningful.
Additionally, achieving adequate statistical power for the biomarker negative subgroup is often not feasible. These factors could limit access to the treatment for biomarker negative patients who might benefit from it. To address these challenges, the authors introduced various statistical methods and conducted numerical studies to compare the performance of several of these methods. They found that a promising approach is a Bayesian Dynamic Borrowing Method that leverages evidence from the biomarker positive subgroup to evaluate the treatment effect in the biomarker negative subgroup. The authors emphasize that any statistical method used for subgroup analysis must be prespecified. Proactive engagement with regulatory authorities and alignment with the guidelines before finalizing study designs and analysis plans are also essential.
The second article is an editorial which accompanies the first article, "Biomarkers in Oncology: Complexities in Biomarker-Driven Studies and Statistical Analysis” by Dr. Hajime Uno and Dr. Miki Horiguchi. In this editorial, the authors introduced additional statistical considerations that can further enhance informed decision making based on the results of biomarker driven oncology clinical trials. Specifically, the authors raised three key points to consider.
Number one is controlling the type 1 error rate. The qualitative assessment of a new treatment involves a statistical test, while regulatory decisions consider the totality of evidence rather than evidence based solely on P values. Statistical tests play a crucial role in determining treatment benefits in each of the three analysis populations, that is, the biomarker positive, the biomarker negative, and the all-comers population. The type 1 error rate of a statistical test is the probability of rejecting the null hypothesis when it is actually true. The threshold for the type 1 error rate is conventionally at 0.05. The threshold value can vary depending on the situation, but maintaining the type 1 error rate at the nominal level is essential to ensure the reliability of the conclusions drawn from a statistical test. Any inflation or deflation of the type 1 error rate from the nominal level can lead to significant issues in regulatory decision making.
Number two is choosing robust and interpretable quantitative summaries of treatment effect. Statistical tests provide a binary outcome aiding regulatory decisions like drug approval. However, quantifying the magnitude of the treatment effect is more informative for clinicians and patients when assessing the risk benefit balance of the treatment. Therefore, the choice of a summary measure to quantify the between group difference is also important. Dr. Wang and colleagues use the Cox Hazard ratio in their study, which is the most common summary measure in oncology trials. Yet this measure relies on several assumptions. Specifically, when it is applied to biomarker driven trials, the proportional hazards assumption must hold in both biomarker positive and biomarker negative subgroups.
In addition, when a stratified Cox analysis is used to integrate the hazard ratio of the two subgroups to derive the hazard ratio for the all-comers population, there is an underlying assumption that the hazard ratios from the biomarker positive and biomarker negative subgroups are the same. These assumptions do not usually hold in practice, and violations of these assumptions can compromise the interpretability of the estimated between group difference and its generalizability to future patient populations. It has also been discussed widely in both statistical and clinical journals that the hazard ratio is difficult to interpret because of the lack of absolute hazards from the treatment and control groups. To address these limitations, Doctors Uno and Horiguchi suggested using alternative summary measures, including restricted mean survival time and average hazard with survival rate, which do not share these limitations and offer more robust and interpretable results than the conventional hazards ratio approach.
Number three is using coherent statistical analysis models for the three analysis populations. In the first article, Dr. Wang and colleagues introduced a Bayesian Dynamic Borrowing approach. The primary analysis of their approach borrowed information from the biomarker positive subgroup only when analyzing the biomarker negative subgroup. They did not perform the borrowing when they analyzed the biomarker positive subgroup. The accompanying editorial highlights the potential bias introduced by this asymmetric approach. Specifically, suppose the treatment effect in the biomaker positive subgroup is pronounced, but that in the biomarker negative subgroup is weaker. In this case, their asymmetric approach produces a more favorable result for the biomarker positive subgroup compared to the symmetric approach, where each subgroup follows the information from the other subgroup. Providing a convincing rationale for using an asymmetric approach or conducting a sensitivity analysis with a coherent approach for both subgroups would be required.
To conclude, biomarker driven oncology trials are diverse and complex, requiring a tailored approach to statistical analysis that considers the unique characteristics of each trial. The Bayesian approach represents one useful analytic approach, but might not be a universal solution for all biomarker driven studies. Further discussions among stakeholders, such as those from regulatory authorities, clinicians, and biostatisticians will stimulate further research on the optimal design and analysis methods for biomarker driven clinical trials in precision oncology.
Thank you for listening to JCO Precision Oncology Article Insights and please tune in for the next topic. Don't forget to give us a rating or review and be sure to subscribe so you never miss an episode. You can find all ASCO shows at asco.org/podcast.
The purpose of this podcast is to educate and to inform. This is not a substitute for professional medical care and is not intended for use in the diagnosis or treatment of individual conditions.
Guests on this podcast express their own opinions, experience, and conclusions. Guest statements on the podcast do not express the opinions of ASCO. The mention of any product, service, organization, activity, or therapy should not be construed as an ASCO endorsement.
In this JCO Precision Oncology Article Insights episode, Fergus Keane provides a summary on "Multi-Institutional Study Evaluating the Role of Circulating Tumor DNA in the Management of Appendiceal Cancers" by Belmont, et al published on May 9th, 2024.
TRANSCRIPT
Fergus Keane: Hello and welcome to JCO Precision Oncology Article Insights. I'm your host, Fergus Keane, an ASCO editorial fellow. Today I will be providing a summary of the article entitled, "Multi-Institutional Study Evaluating the Role of Circulating Tumor DNA in the Management of Appendiceal Cancers" by Dr. Erika Belmont and colleagues.
While appendiceal cancers represent an uncommon diagnosis, the incidence has been rising, with now over 3000 new cases per year diagnosed in the United States. The management of appendiceal cancers includes surgical resection for localized tumors and cytoreductive surgery with hyperthermic intraperitoneal chemotherapy, also known as HIPEC, for select patients with peritoneal metastasis. For patients with higher grade appendiceal cancers, systemic therapy is often included in the treatment paradigm. However, little data pertaining to the optimal treatment regimens exists.
Despite best practice, disease recurrence within three years of surgery will be observed in about 70% of cases of appendiceal cancers. The current conventional methods for surveillance for both detection of recurrence as well as for assessment of response to systemic therapy are using cross sectional imaging and serum tumor markers. These methods are limited and there is a recognition that more accurate biomarkers are required. Circulating tumor DNA, also known as liquid biopsies, refer to shed tumor DNA identified in the plasma. Several ctDNA assays exist, including tumor agnostic assays and tumor informed assays, the latter of which assess presence of personalized tumor derived mutations. The utility of circulating tumor DNA has been studied across several different cancer types and in several different disease settings, for instance in lung cancer and colorectal cancer. However, it has not been well demonstrated to date in appendiceal cancers.
This study aimed to investigate the role of the Signatera ctDNA assay in patients with appendiceal cancer. Specifically, the authors aimed to evaluate factors associated with circulating tumor DNA detection and the association between ctDNA and recurrence free survival after surgery. Their hypothesis was twofold, firstly, that circulating tumor DNA detection would be reduced in patients who received recent systemic therapy, and secondly, that circulating tumor DNA detection after cytoreductive surgery and HIPEC would be associated with a shorter recurrence free survival across all appendiceal cancer grades. The study design was a retrospective review of patients with appendiceal cancers treated at MD Anderson Cancer Center in Texas and the University of Chicago who underwent circulating tumor DNA testing between January 2019 and December 2022. Clinical, pathologic and treatment related information was collected for all patients. Regarding patient treatment, all patients received treatment as per the consensus recommendations at both cancer centers. Diagnostic evaluation was with CT or MRI imaging and serum tumor markers. Diagnostic laparoscopy was performed to evaluate for the presence of peritoneal metastases. The patient treatment plans were determined via MDT tumor board discussions and cytoreductive surgery, and HIPEC was offered with curative intent to eligible patients.
Systemic therapy with 5-FU based doublet or triplet therapy with or without VEGF inhibitors was offered to patients with grade two or three tumors and with a good performance status. HIPEC protocols involved the use of mitomycin C. Postoperative surveillance involved cross sectional imaging and tumor marker evaluation every three months for two years and thereafter every six months if the patients remain disease-free. Circulating tumor DNA testing was offered at the discretion of the treating physician, typically every three months after surgery. The Signatera assay is a personalized, multiplexed, PCR based next generation sequencing platform. Three major analyses were performed. Number one, the frequency of any time ctDNA detection was evaluated in patients with ctDNA assays drawn at the time of radiographic or laparoscopically identifiable disease. Number two, the correlation between preoperative ctDNA levels and intraoperative peritoneal cancer index was evaluated in patients with peritoneal metastases. The third analysis involves the association between circulating tumor DNA presence drawn within one year of optimal resection.
A total of 402 plasma samples were obtained from 94 patients from the two centers. Most patients had grade 2 or 3 appendiceal cancers and 85% underwent surgery. Most patients had peritoneal metastases. 50 patients had circulating tumor DNA assessment in the presence of stage 4 disease, included in this, 13 patients were tested preoperatively, 26 patients who developed recurrence after surgery were included, and 11 patients who did not undergo surgery. In total, circulating tumor DNA was detected in 66% of these patients. The detection frequency was 57.1% in patients with grade 1, 62.5% in patients with grade 2, and 70.4% in patients with grade 3 disease, but this variability did not meet statistical significance. Lower circulating tumor DNA detection was observed in patients who received systemic therapy within six weeks before ctDNA assessment at 43.8% versus 76.5%, and multivariate analysis confirmed this association, demonstrating that recent systemic therapy was associated with an odds ratio of 0.22 versus less recent systemic therapy.
17 patients underwent circulating tumor DNA testing before cytoreductive surgery, and HIPEC and circulating tumor DNA was detected in 23.5% of these cases. No correlation was observed between ctDNA detection and intraoperative PCI index in these patients. Among the 50 patients with ctDNA testing within one year of optimal resection, survival estimates were generated for 36 patients who underwent cytoreductive surgery and HIPEC for grade 2 and 3 appendiceal cancers. The median follow up was 19.6 months. Circulating tumor DNA detection after cytoreductive surgery was associated with a shorter median recurrence free survival of 11.3 months versus not detected in those without ctDNA detection. On multivariate analysis, this was confirmed. The median time interval between surgery and ctDNA detection was 31 weeks. In this cohort of 36 patients, 44.4% or 16 patients developed disease recurrence.
During the surveillance period, ctDNA was elevated in 93.8% of these patients, demonstrating a higher sensitivity than CEA, CA 19-9 or CA 125 tumor markers. Only one patient with disease recurrence had negative ctDNA at that time. Among these 16 patients with disease recurrence, one patient with a positive ctDNA test had their first sample drawn after diagnosis of disease recurrence, and one patient who had extensive adjuvant systemic therapy developed ctDNA negative recurrence. In the remaining 14 patients, circulating tumor DNA detection preceded the diagnosis of recurrence on imaging by a median of 11 weeks.
In summary, this study is a large, retrospective report of tumor-informed circulating tumor DNA testing in patients with appendiceal cancers. This study is one of the first to elucidate the factors associated with circulating tumor DNA detection in this disease and a potential role for circulating tumor DNA as an adjunct tool in the surveillance of patients with this malignancy.
Again, I'm Fergus Keane, a JCO Precision Oncology Editorial Fellow. Thank you for listening to the JCO Precision Oncology Article Insight. Please tune in for the next topic. Don't forget to give us a rating or review, and be sure to subscribe so that you never miss an episode. You can find all ASCO shows at www.asco.org/podcasts.
The purpose of this podcast is to educate and to inform. This is not a substitute for professional medical care and is not intended for use in the diagnosis or treatment of individual conditions.
Guests on this podcast express their own opinions, experience, and conclusions. Guest statements on the podcast do not express the opinions of ASCO. The mention of any product, service, organization, activity, or therapy should not be construed as an ASCO endorsement.
JCO PO author Dr. Samuel J. Klempner shares insights into his JCO PO article, “PD-L1 Immunohistochemistry in Gastric Cancer: Comparison of Combined Positive Score and Tumor Area Positivity across 28-8, 22C3, and SP263 assays”. Host Dr. Rafeh Naqash and Dr. Klempner discuss assessing the analytical comparability of three commercially available PD-L1 assays and two scoring algorithms used to assess PD-L1 status in gastric cancer samples.
TRANSCRIPT
Dr. Abdul Rafeh Naqash: Hello and welcome to JCO Precision Oncology Conversations, where we bring you engaging conversations with authors of clinically relevant and highly significant JCO PO articles. I am your host, Dr. Abdul Rafeh Naqash, Social Media Editor for JCO Precision Oncology and Assistant Professor at the OU Health Stephenson Cancer Center. Today we are excited to be joined by Dr. Samuel J. Klempner, Director of Gastro Esophageal Medical Oncology and Assistant Professor at Harvard Medical School Mass Gen Cancer Center and author of the JCO Precision Oncology article, “PD-L1 Immunohistochemistry in Gastric Cancer: Comparison of Combined Positive Score and Tumor Area Positivity Across 28-8, 22C3, and SP263 Assays.”
At the time of this recording, our guest disclosures will be linked in the transcript.
Dr. Klempner, welcome to our podcast and thanks for joining us today.
Dr. Samuel J. Klempner: Happy to be here. Thanks for having me.
Dr. Abdul Rafeh Naqash: For the sake of this podcast, we'll be using our first names. So, Sam, it was great to see you at ASCO recently, where I believe you presented these data as an abstract as well.
Dr. Samuel J. Klempner: Yes, we had a poster presentation for this paper, which was published in parallel with the meeting.
Dr. Abdul Rafeh Naqash: Congratulations, and I'm very happy that you chose JCO PO as the destination for these data. So we're going to be talking about a lot of different things today in the context of gastric cancer, which I know you treat very often in your clinic. So could you tell us what the treatment landscape for advanced gastric cancer currently is? Because that goes into the context of why I believe you and your colleagues went ahead with this project.
Dr. Samuel J. Klempner: Yeah, happy to. As you know, unfortunately, half or more of our patients, by the time they come to medical attention for a gastric or GE junction or esophageal adenocarcinomas, unfortunately have advanced disease, often metastatic at presentation. So we have this large population of patients with advanced disease, and over the last couple years, we've actually made some substantial advances in the management and survival of this population. This has been mainly driven by biomarker selection, whether it be adding immunotherapy on top of HER2 therapy, whether it be testing for claudin and seeing the results with claudin directed therapies. And perhaps the vast majority of patients are potentially eligible for immune checkpoint inhibitors. We've seen several phase three trials, perhaps highlighted by CheckMate 649, KEYNOTE 859, rationale studies confirming that there are populations of patients who derive significant survival advantages from the addition of anti PD-1 on top of chemotherapy. So the landscape has really evolved into a biomarker directed world, which is exactly what we hope, because ultimately, the goal is, of course, to match patients with the best drugs at the right time. And that's really the background of where this analytical effort came from.
Dr. Abdul Rafeh Naqash: Thank you for giving us that overview. Going to the second part, which, as you mentioned in your initial overview about the role of immunotherapy, and as we all know, immunotherapy has changed the treatment landscape for a lot of different tumor types. And as clinicians, we often see or ask, what is the PD-L1 positivity for, let's say, lung cancer, which is what I treat, and gastric cancer, which is what you treat. Some of the nuances that we don't necessarily go into when we're looking at those reports is the combined positivity score, the tumor proportion score, or the tumor area positivity. Could you give us an understanding, for the sake of our audience or for the sake of our trainees who might be listening to this podcast, what the CPS, or what the TAP mean and where they are used in the treatment landscape for biomarker selection in the context of gastric cancer? And how do you approach the different cutoffs for CPS when you're treating an individual in the standard of care setting for gastric cancer?
Dr. Samuel J. Klempner: For sure, happy to. So I think eventually it all comes back to patients. When we're sitting in a clinic room with the patient, we want to be able to have features about the tumor that's going to tell us if a therapy is more or less likely to work, maybe if there's a prognostic implication so we have predictive and prognostic biomarkers. And PD-L1 expression does not appear to be particularly prognostic, but it does appear to be predictive of benefit from immune checkpoint inhibitors. Therefore, all of the phase 3 trials that we've seen in some way have linked the biomarker expression to outcomes, whether it's the primary endpoint, whether it's post hoc retrospective analyses, etc. What we've seen is that all of these phase 3 trials have largely used different antibodies to define PD-L1 strata within the trial. So whether that's 22C3, whether it's 28-8, whether it's 263, those are the predominant antibody clones used to examine PD-L1 expression in tumor samples. And it's been pretty clear across these large phase 3 trials that there is a trend with increasing PD-L1 expression and increasing magnitude of benefit. We see this in the improved hazard ratios in the CPS greater than five or greater than ten versus less than one, etcetera.
However, the scoring systems have varied. There is TPS tumor positivity, which only accounts for tumor cells. There is combined positive score, which accounts for tumor cells and mononuclear infiltrates and involves counting cells. And then perhaps the most recent one is the tumor area positivity, which is essentially a non counting method to look broadly at the area of the sample that is expressing PD-L1. It was on this background that we said, is there analytical concordance among the main antibodies? Our work does not address whether there is difference in clinical outcomes between testing 28-8 and 22C3 and SP263. It is simply a pure analytical comparison of the three antibodies. Is a CPS 5, when you call it by 28-8, somewhat agreeable to a TPS or a TAP greater than five with the same antibody and with a different antibody. So we felt that this was kind of a question that hadn't really been fully addressed in the field and may help contextualize results for clinicians and ultimately cross trial comparisons.
Dr. Abdul Rafeh Naqash: Thank you for that explanation. And you bring forth a very important question. And I remember this example of a patient with lung cancer who had tissue NGS done, and they had a limited gene panel with PD-L1 testing sent that showed a PD-L1 of close to 15 or 20%, and then another NGS panel with a different antibody, suggesting that they had a PD-L1 of close to 60-70%, which significantly changes the overall approach for treatment in the context of blood cancer. Is that something that you experience in gastric cancer also, in terms of variability for CPS, determining what treatment combinations you might be able to put an individual patient on?
Dr. Samuel J. Klempner: It's rare that we have samples at any institution tested in multiple methods, but these types of papers and others had looked at some stuff similar and prior to our publication, but we know that there is both spatial heterogeneity. So if you test a tumor versus metastasis, you may have different PD-L1 scoring even in regions of large samples, like surgical resections, there will be some intra tumor heterogeneity in regions of expression. And then we also know that sometimes after therapy, for example, post radiation, there's some data that at the time of surgery, the PD-L1 expression may be higher than what the presurgical sample was. So there's a lot of variables that are factored in. But one thing that wasn't really well known is, across the standard antibodies, how well is the inter assay comparison? There had been some work from a group in Singapore, a very nice paper suggesting that at the higher cut points, the agreement was pretty good across the assays, CPS greater than 5 and greater than 10, and maybe slightly less so at the lower. They had used a different method, which was not really what is standard, and they had used multiplex immunofluorescence or IHC. This is not a validated method for PD-L1 scoring. So that was an open question, sort of. Although they laid a very important piece of data down, we wanted to use the most standard assays and essentially do a very similar analysis, but using the standard scoring criteria.
Dr. Abdul Rafeh Naqash: Very interesting. So, could you walk us through the approach of how you looked at this question, what kind of samples you used and what kind of testing algorithms you implemented to look at the cross validation of these three different antibodies?
Dr. Samuel J. Klempner: The antibodies were chosen primarily because those are the standard ones that either have companion diagnostics or have been used most commonly in phase 3 trials. So 22C3 has most commonly been linked to pembrolizumab, 28-8 to nivolumab, and 263 used with Roche and Genentech trials primarily. And so we selected the antibodies based on the common use. We selected the scoring systems of CPS and TAP, again based on the most commonly used and validated scoring algorithms in gastric cancer. And then, although most patients in clinic and metastatic disease present with biopsy samples from the primary tumor, there may be some limitations in biopsy samples in terms of small amount of material and ability to reliably count 100 cells, etc., for CPS. So we actually use surgically resected samples from a commercial biobank, 100 samples, and essentially 28-8 was really the reference. And we picked samples that, using 28-8 CPS PD-L1 expression represented the entire spectrum, meaning we had CPS less than 1, we had greater than 1 and less than 5, greater than 5 and less than 10, and greater than 10, so that we could compare across these different strata, because those are the most common strata that have been used in clinical trials and linked to magnitude of benefit.
Dr. Abdul Rafeh Naqash: And something that, interestingly, I see here when we go to some of the results, and I'm pretty sure you'll talk about the concordance, is the correlation coefficient seems to increase as the percentage positivity increases for a certain antibody. Could you try to help us understand why that might be the case? Is it because it's easier for the pathologist to look at the slide when there is a certain level of positivity that crosses a certain threshold? Or could there be some other factors that are not well understood.
Dr. Samuel J. Klempner: Yeah, it's a totally good question, and I think it's something that's seen in other IHC biomarkers as well. If you look at HER2, you'll see some similar trends. The agreement at IHC 3+ is pretty good and greater than it is at lower cut points. And having talked to multiple pathologists, and I'm not a pathologist, we had three pathologists scoring all of these samples, and essentially, it's what you might expect. It is just easier when there's a lot of the marker. It is easier to judge the high extremes of the strata. So the agreement at greater than 10 is quite good, and this has already been shown by others. It's just an easier thing to score for anyone. The agreement is better across all of the assays at higher cut points, whether it's TAP greater than 10% or CPS greater than 10%. And you can see that pretty clearly in our data, and it's also been shown in other data sets looking at roughly similar questions in other tumor types.
Dr. Abdul Rafeh Naqash: Going to the interesting results that you have in this paper, could you highlight for us some of the important findings that you had and put them into context of what their clinical implications may be?
Dr. Samuel J. Klempner: Yeah, I think I'll start with the clinical implications so that what clinicians, and we're both clinicians, what we want to know is, if I have a report that says the CPS is greater than 1 and it's done with a 22C3 test, is that also likely to be greater than one if it had been done with a 28-8 test or scored with a different algorithm - CPS versus TAP? So, essentially, some degree of confidence on the interchangeability between the assays themselves, that is really the clinical implication. And so, to accomplish this, we set out to basically do the comparisons you'd have to do to convince yourself that that is true. So you take samples against a reference range, in this case, across the PD-L1 strata, you pick a reference test, in this case, 28-8, you have one pathologist be the start, and then you compare other pathologists against each other and that person, and you look. And in the pathology literature, they have strata of agreement which tend to go from poor, moderate, good to excellent. And these are sort of accepted standards in the pathology world about inter reader agreement. So between one pathologist and another, and things that are moderate or good are considered essentially acceptable at interchangeable levels.
And so, as you suggested, at the higher cut points, the agreement is very good. The clinical interpretation of that is that if you get a TAP greater than 10% scored on a 22C3 antibody on a Dako staining system, you can feel relatively confident that that would also be called a TAP or a CPS greater than 10 by a 28-8 antibody, suggesting there is good agreement between the two antibodies at that cut point. As you move down, there is a little bit less agreement, and that is consistent with what's been shown before. But in our data set, the agreement was still pretty good across all three of the antibody clones, even at the lower cut point, so greater than 1% for TAP or CPS greater than 1. And that provides, I think, some reassurance to clinicians that whatever test their own pathology lab is using, if it's one of these three assays, they can provide some degree of confidence that what they're seeing would be similar to what they were seeing if it had been done with another test.
Dr. Abdul Rafeh Naqash: I think that that is very important, because even though we do want broad testing in general for metastatic tumors, as you probably will agree with, but there's a lot of practices still that institutions tend to do their own testing with limited gene panels or even IHCs. So I think to put that in the context of your study, as you said, if you have a certain antibody that is positive, as you've shown, then that also likely means that with another antibody that your institution may not test for, it's likely the tumor sample is likely going to be positive at a similar level.
So I think you also used digital pathology as part of this project, even though that may not be the most important aspect. As we move slowly and steadily towards artificial intelligence and machine learning, could you tell us how you incorporated the digital assessments and how you utilize them to correlate with the pathologist assessment and the futuristic perspective of how we could eventually try to incorporate digital pathology assessments for this kind of staining approach, which might limit interobserver operability differences as well as time constraints?
Dr. Samuel J. Klempner: I hope I can do this part justice, because, again, I'm not a pathologist. But the digital imaging analysis was really essentially used as a quality check and verification tool in our own paper. Our intent was not to establish DIA directly as a superior methodology to TAP or CPS, but simply to provide ourselves some degree of confidence in the staining pattern and distribution across the three assays, and whether or not this would generate significant differences in what the PD-L1 score would have been called. And so, the bottom line is, the digital imaging analysis suggested there were very minor differences across the three assays in terms of, like, percent cell positivity, which is one of the main readouts, and the mean difference was actually quite small. So we felt that the digital imaging analysis, which was really considered somewhat exploratory in our own work, supported what we saw with the pathology comparators read in traditional methods. I think it sets somewhat of an initial pilot data benchmark to say that maybe we can think about moving tools like digital imaging analyses forward in terms of PD-L1 scoring approaches in the future. But it does not provide adequate data to say that we can do this now or we have enough samples and enough comparisons to say that, “Hey, for sure, digital imaging is equivalent to pathology reading.” I think that we're getting there and our data supports that that may ultimately be the conclusion, but for us it was really essentially an orthogonal support and sanity check for our traditional approach, which is, of course, a pathologist based scoring. So supportive and suggestive, but not definitively conclusive.
Dr. Abdul Rafeh Naqash: Definitely early days for visual pathology assessments, but I think that it's a very rapidly evolving field, and hopefully we'll see more of this in the next few years, as well as incorporating some assessments into clinical trials.
Now, shifting away from your honorary pathologist role as part of this project to your actual role as a clinician investigator/clinician scientist, could you tell us your career trajectory, how you started, how you've self paced yourself, and how you've tried to mentor certain different individuals in your current role?
Dr. Samuel J. Klempner: Yeah, I remember my grandfather and other people telling me, just try to leave it a little bit better than you found it. And so that's, I think, a guiding principle. I hope that at the end of my own career, I can leave oncology a little bit better than when I started. I think the best way to do that is to mentor and train the next generation who are going to drive these practices. I started, like many others, personally touched by cancer in my family, which started me on a journey towards oncology, was somewhat frustrated by the lack of options available to my mom, and then became deeply interested in the science and how come we knew so little about cancer, so spent a fair amount of time in labs, and had a really formative experience with Lew Cantley looking at PI3 kinase resistance and signal transduction, and wanted to learn to speak the language and interact with people driving the lab based work. And that's been something I've tried to keep as central to my career as someone who has a very strong translational interest.
And so I try to think of ways that I think we can learn from every single patient and every subgroup. I mean, for example, in our own work here, it's very unclear if there's a biology linked to the different PD-L1 strata. So for example, does a PD-L1 CPS greater than 10 tumor have a very high interferon gene signature? Or are there features of the T cells that are different between a CPS 10 or higher versus a less than 1? So PD-L1 is a biomarker, but is it really telling us about biology? And so these are the types of questions that I try to stimulate in all the residents and fellows and hopefully it will drive translational projects. But I think just having the conversations and asking the questions and talking to people. I mean, I love the ASCO Career Lounge and always try to do that when possible. I know you do the same. I think staying curious is really the thing that I try to remain in life and also in my career and have fun and enjoy with your colleagues. And I think that will make us all better researchers and ultimately translate to better outcomes for our patients, which is, of course, why we all do this.
Dr. Abdul Rafeh Naqash: Wonderfully said Sam, thank you so much. Thanks again for choosing JCO PO as the final destination for your work. Hopefully we see more of the similar work that you do in your field in JCO PO. And thank you for talking to us about your journey as well.
Dr. Samuel J. Klempner: Yes, thanks for having me. I'll talk to you sometime soon.
Dr. Abdul Rafeh Naqash: Thank you for listening to JCO Precision Oncology Conversations. Don't forget to give us a rating or review, and be sure to subscribe so you never miss an episode. You can find all ASCO shows at asco.org/podcast.
The purpose of this podcast is to educate and to inform. This is not a substitute for professional medical care and is not intended for use in the diagnosis or treatment of individual conditions.
Guests on this podcast express their own opinions, experience and conclusions. Guest statements on the podcast do not express the opinions of ASCO. The mention of any product, service, organization, activity or therapy should not be construed as an ASCO endorsement.
Disclosures
Dr. Klempner
Stock and Ownership Interests TP Therapeutics Nuvalent, Inc
Honoraria Merck Serono
Consulting or Advisory Role Atellas Pharma Bristol-Myers Squibb Merck Daiichi Sankyo/UCB Japan Sanofi/Aventis Mersana Exact Sciences Novartis SERVIER AstraZeneca Amgen I-Mab iho Oncology
In this JCO Precision Oncology Article Insights episode, Mitchell Elliot provides a summary on "Serial Postoperative Circulating Tumor DNA Assessment Has Strong Prognostic Value During Long-Term Follow-Up in Patients With Breast Cancer" by Shaw, et al published on May 1st, 2024.
TRANSCRIPT
The guest on this podcast episode has no disclosures to declare.
Mitchell Elliott: Hello and welcome to the JCO Precision Oncology Article Insights. I'm your host, Mitchell Elliott, an ASCO Journal editorial fellow. Today I will be providing a summary of the article titled, “Serial Postoperative Circulating Tumor DNA Assessment Has Strong Prognostic Value During Long Term Follow up in Patients with Breast Cancer,” by Dr. Jacqueline Shaw and colleagues.
Circulating tumor DNA is shed readily into the peripheral blood by tumors. ctDNA makes up a small fraction of the total cell free DNA in the peripheral blood and can be detected using highly sensitive assays. ctDNA assays can be tumor-informed where blood samples are tested for the presence of tumor specific mutations, which are selected by sequencing the primary tumor, so the panels are patient specific. Tumor agnostic assays also exist which are typically looking for the presence of cancer driver mutations or cancer derived methylation signals, which are not patient specific but rather cancer specific. Several retrospective analyses of clinical trials and cohorts have demonstrated that the identification of ctDNA in patients in follow-up can predict relapse in breast cancer, lung cancer, and colon cancer. Personalized tumor informed assays have demonstrated high technical specificity, but to date there is no gold standard assay identified and no direct comparison between all of the available assays. While the literature to date has demonstrated that identification of ctDNA prior to clinical relapse is possible, no study has demonstrated that it improves patient outcomes.
In this specific study, the authors evaluated the Signatera assay, a tumor informed assay based on whole exome sequencing, enabling the design of personalized panels for up to 16 tumor specific variants detected via multiplex PCR next generation sequencing. This was evaluated in the exploratory breast lead interval study or EBLIS, which is a study based out of the United Kingdom. EBLIS is a multicenter prospective cohort study funded by Cancer Research UK and the National Institute of Health Research that opened for recruitment in 2012. This was a retrospective analysis so no results were directly shared with patients or physicians. Patients were eligible if they were 18 years or older, had histologically confirmed breast cancer and must have completed all surgery and chemotherapy within three years of entry into the study. They had to have an adjuvant online risk relapse at greater than 65% or mortality of greater than 50% at 10 years, which defines a very high risk subgroup for study enrollment.
The results of this study and the baseline patient characteristics reflected the predefined clinical risk. The majority received neoadjuvant or adjuvant chemotherapy. Most patients were diagnosed with invasive ductal carcinoma and were staged 2b to 3c. There were 156 patients identified from this cohort after 28 had insufficient DNA and 3 had unsuccessful whole exome sequencing, which are required for the assay generation. Of the 156 patients, there were 1136 plasma time points evaluated. Of the 1136 plasma time points, ctDNA was identified in 46, which represents approximately 4% of the total time points in this high risk cohort. 34 patients have experienced disease relapse, including 22 with hormone receptor positive HER2 negative disease, three with hormone receptor positive HER2 positive disease, seven with triple negative breast cancer, and two with hormone receptor negative HER2 positive disease. ctDNA was detected in 30 of the 34 patients who had a subsequent relapse with a patient specific sensitivity of 88.2%. Relapse was predicted with a lead time interval of up to 38 months with a median of around 10.5 months ranging from 0 to 38 months. 100% of relapses were detected through ctDNA in patients with hormone receptor positive HER2 positive disease, triple negative breast cancer and hormone receptor negative HER2 positive disease.
Patients with a positive ctDNA test had a poor recurrence free survival with a hazard ratio of 52.98 with a 95% confidence interval of 18.32 to 153.2 with a statistically significant p value. Patients also had a significantly reduced overall survival if ctDNA was detected in the adjuvant setting. Multivariate models incorporating clinical pathologic variables and ctDNA status were analyzed. In this, ctDNA status remained the most significant factor associated with recurrence free survival and overall survival. Interestingly, concurrent ctDNA analyses and CA 15-3 measurements were available for 100 patients. CA 15-3 status was defined as positive and negative at the cutoff value of 30 units per milliliter. A Fisher's exact test showed a borderline statistically significant correlation between ctDNA status and CA 15-3, with a p value of 0.053. Again, multivariate analyses indicated that ctDNA was independent of CA 15-3 in predicting recurrence free survival and overall survival. Interestingly, ctDNA was not detected in 4 patients who experienced subsequent disease relapse, even with consistent and frequent sampling. Furthermore, ctDNA was detected in 5 out of 122 patients who did not have a subsequent recurrence, all being hormone receptor positive HER2 negative. These patients also had mature follow up. It is unknown if there was a change in the adjuvant treatment associated with subsequent negative tests, and follow up continues.
In summary, the study reaffirms that personalized ctDNA assays have high technical sensitivity and specificity for the identification of patients at risk for disease relapse. The test is highly predictive of recurrence in patients with breast cancer, especially with triple negative subtype where all patients had ctDNA detected prior to clinical relapse. However, for patients with hormone receptor positive breast cancer, these results suggest that this test needs to be used with caution, as a small proportion of patients experience disease relapse with negative tests and others whose tests are positive have not yet relapsed. It is unknown if these patients with ctDNA detected have radiographically overt metastatic disease in the absence of clinical symptoms, as concurrent radiographic surveillance was not performed in the standard of care follow up. Prospective clinical trials are required to define a role for ctDNA surveillance in clinical care.
Again, I'm Mitchell Elliot, a JCO Precision Oncology editorial fellow. Thank you for listening to the JCO Precision Oncology Article Insight, and please tune in for the next topic. Don't forget to give us a rating or review and be sure to subscribe so you never miss an episode. You can find all ASCO shows at www.asco.org/podcasts.
The purpose of this podcast is to educate and to inform. This is not a substitute for professional medical care and is not intended for use in the diagnosis or treatment of individual conditions.
Guests on this podcast express their own opinions, experience, and conclusions. Guest statements on the podcast do not express the opinions of ASCO. The mention of any product, service, organization, activity, or therapy should not be construed as an ASCO endorsement.
JCO PO author Dr. Jun Gong shares insights into his JCO PO articles, “Phase II Study of Erdafitinib in Patients with Tumors with FGFR Amplifications: Results from the NCI-MATCH ECOG-ACRIN Trial (EAY131) Sub-protocol K1" and “Phase II Study of Erdafitinib in Patients with Tumors with FGFR Mutations or Fusions: Results from the NCI-MATCH ECOG-ACRIN Trial (EAY131) Sub-protocol K2”. Host Dr. Rafeh Naqash and Dr. Gong discuss the limited activity of FGFR inhibition in solid tumors with FGFR amplifications and mutations or fusions in this NCI-MATCH phase II trial.
TRANSCRIPT
Dr. Rafeh Naqash: Hello and welcome to JCO Precision Oncology Conversations, where we bring you engaging conversations of clinically relevant and highly significant JCO PO articles. I'm your host, Dr. Rafeh Naqash, Social Media Editor for JCO Precision Oncology and Assistant Professor at the Stevenson Cancer Center at the University of Oklahoma.
Today, we are excited to be joined by Dr. Jun Gong, Associate Professor in the Division of Medical Oncology at Cedars-Sinai Medical Center and lead author of the JCO Precision Oncology article entitled "Phase II Study of Erdafitinib in Patients with Tumors Harboring FGFR Amplifications: Results from the NCI-MATCH ECOG-ACRIN Trial EAY131 Subprotocol K1" and "Phase II Study of Erdafitinib in Patients with Tumors with FGFR Mutations or Fusions: Results from the NCI-MATCH ECOG-ACRIN Trial EAY131 Subprotocol K2."
Our guest's disclosures will be linked in the transcript.
Dr. Gong, welcome to our podcast and thank you for joining us.
Dr. Jun Gong: Thank you, Dr. Naqash and JCO Precision Oncology for having me.
Dr. Rafeh Naqash: We are excited to be discussing some interesting aspects that you have led and published on from the NCI-MATCH trial. We were trying to understand from a background perspective, since this master protocol has been going on for quite some time, could you give us a little bit of background for the sake of our listeners on what the NCI-MATCH is and what were the specific objectives for these two subprotocols?
Dr. Jun Gong: Yes, of course, Dr. Naqash. So, as you may all know, the importance of targeted therapies in the current era of precision oncology. And on that backdrop, the NCI-MATCH was a national multicenter study designed essentially to look for signals of efficacy across various solid tumor and hematologic malignancy types, with a focus on specific mutations. The master protocol is unique in that there are several arms to the trial, each targeting a specific potential targetable alteration using available agents in cancer today.
Dr. Rafeh Naqash: Excellent. Thank you for that background. I know this master protocol has been going on for quite some time with different subprotocols. I believe some of them are immunotherapy-based. Also, you've led two important subprotocols, which are the FGFR amplification and the FGFR mutation or fusion. There are some differences, from what I gather, in responses for the fusions versus the amplifications or mutations versus the amplifications. Could you first delve into the first paper of the fusions, and describe what were the tumor types? As you mentioned in the paper, some tumors were excluded. What was the reason for the exclusion of some of those tumor types? Why did you want to study the fusions and mutations versus the amplifications separately? What was the background for that? Could you highlight some of those points for us?
Dr. Jun Gong: Firstly, as a kind of a more background, FGFR has been a recognizable target for a couple of tumor types. And if you look at the broad landscape of FGFR alterations, they occur in about 5%-10% of cancers, with the majority being FGFR amplifications actually, and mutations and rearrangements following second and third respectively in most commonly identified alterations. With that being said, FGFR mutations and rearrangements have already been established in a couple of tumor types. Actually, the first FDA approval for an oral FGFR inhibitor was erdafitinib, which was the agent used in both of these back-to-back trials. However, erdafitinib was first approved in urothelial carcinoma, and since then, there has been an explosion in oral FGFR inhibitors targeting fusions and mutations in other cancer types, such as cholangiocarcinoma.
More recently, there was even an FDA approval in a myeloid malignancy as well. So, we used erdafitinib, being that it was the first FDA-approved, orally available agent to target this alteration. We conducted the two back-to-back studies in recognition that although rearrangements and mutations have already been established in certain tumor types, we were more interested in looking at the more common FGFR alteration, that being amplifications. However, the efficacy in that was a little unknown, and so these two separate subprotocols were developed: K2, which was to look at FGFR mutations and fusions in tumor types, excluding urothelial carcinoma, to look if there was a signal of efficacy beyond currently FDA-approved indications, and amplification as a separate cohort.
Dr. Rafeh Naqash: That's a very good explanation of why you concentrated on the tumor types in these protocols.
Now, going back to subprotocol K1, could you tell us what were some of the tumor types that you did include, and what was the sample size, and what was the hypothesis for the sample size as a meaningful level of activity that you wanted to see and would have potentially led to a bigger, broader trial?
Dr. Jun Gong: So, subprotocol K1 was the arm investigating erdafitinib in those with FGFR amplifications, and these were predefined on the NCI-MATCH protocol, looking at FGFR 1, 2, 3, and 4 amplifications essentially. These were allowed to have local testing through a local CLIA-certified assay, but then they needed to be confirmed on a central assay, which is the NCI-MATCH Oncomine assay. These statistics are uniform for the NCI-MATCH trials, and the goal was at least 31 patients, with the hypothesis that if the response rate was 16% or more, this was considered a signal of activity. However, there was an additional protocol specific requirement in that if the sample size was fewer than 31 patients, then the primary efficacy population would be assessed against a null hypothesis overall response rate of 5%. Meaning that if there were less than 31 subjects, an overall response rate of greater than 5% would be defined as positive. Again, the NCI-MATCH was uniform. Secondary objectives included progression-free survival, overall survival, and safety and toxicity. With that being said, K1 originally began accrual. The NCI-MATCH actually launched in 2015, but in the subprotocol K1, 35 patients were initially enrolled in the study. If you go down the eligibility criteria, however, a lot of these patients dropped out due to a lack of central tumor confirmation and various reasons. Ultimately, 18 patients were included in the pre-specified primary efficacy cohort.
Dr. Rafeh Naqash: Thank you. I did see for subprotocol K1, you mostly had stable disease in a couple of patients, no responses, and I think one individual with breast cancer had a prolonged stable disease.
Now, from an FGFR amplification standpoint, did you or were you able to correlate - again, this is not objective responses, it's not a partial response or a complete response - was there any correlation from the level of amplification to the duration of stable disease?
Dr. Jun Gong: That's actually the core of our discussion about why K1, despite a variety basket of solid tumor types, somewhere, preclinical data had suggested FGFR amplifications could be targeted, that K1 was ultimately a negative trial with a 0% response rate. We dive in that although we included as an eligibility criteria a copy number variation of seven as the threshold for amplification, we realized that if you look at some of the literature out there, that even in the FGFR 1 and 2 amplification cohorts, where these are the more common cohorts of amplified tumor types that have been targeted, you really needed a high level of amplification, more than 99% of tumor cells being amplified in the previous studies, to actually generate a response.
The thought was that we assumed that FGFR amplification would lead to protein expression and dependence on FGFR signaling, providing sensitivity to FGFR inhibition. However, we realized that there is a certain degree where a high level of amplification needs to happen, and it may not be for all FGFR amplifications. We looked into the literature that FGFR 1 and 2 were the more commonly studied FGFR amplifications. FGFR 1, if you actually look at the amplicon structure, it tends to amplify a lot of other genes because it's such a huge amplicon structure. But FGFR 2 is shorter and centered on just FGFR 2 with a few other genes co-amplified. So, actually in the literature, they've already been seeing that maybe FGFR 2 amplification tumors are more readily targetable based on the robustness of evidence, rather than FGFR 1. But across all of these, the higher the level of amplification, seems the more targetable.
Dr. Rafeh Naqash: Those are interesting discussions around protein expression on the tumor that could imply therapeutic vulnerability. So I've always thought about it, whether trials like NCI-MATCH trials or ASCO TAPUR, for example, would be perhaps more informative if, on a secondary analysis standpoint, proteomics is something that could be done on the tumor tissue, because similar to NCI-MATCH, ASCO TAPUR has other sub protocols where some of these mutations or amplifications don't necessarily result in antitumor responses. But I think from a biology standpoint, as you mentioned, a certain amplification might correspond to RNA expression and that might correspond to protein expression, which is downstream. So looking at that would be something interesting. Have you planned for something like that on these tumor specimens? If you have biobanked any of those specimens.
Dr. Jun Gong: I think that's a great future direction. And I know you, Dr. Naqash, being involved in so many cooperative trials, I think it is possible, but it really depends on good trial planning from the onset. When designing such massive trials like this, I think the more important thing is if your trials are negative, but they are informative for the field to go back and have these postdoc available biobanks that you said. And I think having it integrated firstly, is way more efficient than to have kind of an amendment kind of going through halfway or when the trial is started. That could be a little bit more logistically difficult.
Dr. Rafeh Naqash: I completely agree. And you mentioned corporate groups, I think we've been discussing, and I'm pretty sure you have also, there's a lot to be learned from clinical trials that are negative. We often, in the academic or non-academic setting, end up not publishing some of those negative results, pharma or corporate group based studies. And I think the resources, the specimens, and the negative results could correlate to some other novel findings if some of those exploratory analyses are done in the appropriate manner.
Now, going to the drug itself or the erdafitinib here, it's a pan-FGFR inhibitor. Is that something that you think is a limitation in the drug development space? I do early phase trials, and I'm pretty sure you do a lot of these basket early phase trials. Is that something that you feel is a limitation when you have a drug that targets different mutations or different protein changes of the same gene or different amplifications? Could that be a reason why something like this doesn't necessarily work because it doesn't have as much specificity against the isoform as one might need to inhibit the downstream kinase activation?
Dr. Jun Gong: That is also a great point. The NCI-MATCH sub protocol K1 and K2 used erdafitinib, which was the first FDA-approved FGFR inhibitor. But as many of the listeners and yourself may know, there have been newer iterations in next-generation development of the FGFR inhibitors. And it's very fascinating, the tyrosine kinase inhibitors, with each iteration, you seem to have a little more potency and the ability to bypass some of the resistance mutations, almost paralleling the lung cancer space, where we kind of follow that, and they've been kind of the pioneers in that space. And to your point, yes, we consider– the NCI-MATCH was developed nearly a decade ago, and the available agents at that time, would it have changed the findings if we used a kind of a newer generation or more potent FGFR inhibitor? It's possible, I think, especially in the K1 cohort with the amplifications. We even suggested in the discussion of the paper future directions, is that one way to kind of bypass the amplification issue is to use more potent and specific FGFR inhibitors. And so I think it's very possible that you highlight this point.
Dr. Rafeh Naqash: And for the sake of our listeners, Jun, especially trainees, could you highlight what are currently some of the FDA-approved FGFR inhibitors, and what tumor types are they currently approved in?
Dr. Jun Gong: The first one, as we have hinted, was in treatment of refractory, essentially urothelial carcinoma with FGFR mutations and rearrangements, mainly 2 and 3. And this is where oral erdafitinib was approved. And it's interesting, I kind of teach my fellows and our health staff that erdafitinib is interesting in that its FDA label insert requires a starting dose of about 8 milligrams daily, and it's a 28-day cycle. But during the first 14 days, we're really looking at the serum phosphate levels. If they are within a certain level, if they are within 5.5 to 7, for example, you continue the current dose. But if they are less than 5.5, the FDA label actually mandates that you increase it to 9 milligrams oral daily, continuously. This is biologically logical to me. FGFR is located to the renal tubules, and so this is a major phosphate kind of metabolism pathway here. And so you're using that as a surrogate, essentially, if the right dosing is achieved. And so that's unique.
And then the subsequent kind of FGFR inhibitors that came about, you had a couple in cholangiocarcinoma, where, unlike urothelial carcinoma, where it's about 30% of the time, you'll find the FGFR alterations of target. It's about half of that 15% in cholangiocarcinoma, and it's mainly intrahepatic cholangiocarcinoma in that sense. And here you have pemigatinib, which is one of the FGFR inhibitors approved for cholangiocarcinoma. And then you also had infragatinib, which is approved. But however, infigratinib eventually had their FDA label culled. It was withdrawn by the company, I think it was in 2022. And then more recently, you had even a more potent FGFR inhibitor in cholangio approved and futibatinib. It's interesting that with these more later generations of FGFR inhibitors, they do show a correlation with phosphate levels, but they don't have that specific kind of dosing early on in the first cycle, like erdafitinib. And so it's interesting to see that with the later generations, you're seeing more potency as well.
Dr. Rafeh Naqash: Thank you for that overview, which I'm sure most of the trainees appreciate since this is an up and coming field in the space of precision medicine, especially FGFR. From a side-effect profile standpoint, you mentioned phosphate issues. Do you think that is a drug class effect here, or is that an FGFR receptor subtype effect, depending on which FGFR receptor, 1 or 2 or 3, that is being targeted?
Dr. Jun Gong: I do think this is a class effect that you'll see across a lot of the trials where phosphorus elevations or decreases are going to be probably your most common treatment-related adverse event. And I actually emphasize this is probably one of the most trickier side effects of this class, where we’re almost having to have to monitor the phosphorus levels pretty routinely, pretty closely. And you also have other class effects on the nails. There's some rare retinal ocular toxicities that's unique to the FGFR class as well. And so it's a very exciting class of compounds, but it does require some close monitoring of some unique class effects as you’ve hinted.
Dr. Rafeh Naqash: Based on the results from your K1 sub protocol, are FGFR inhibitors still the approach within, let's say, within cholangio or urothelial with FGFR amplifications? Is that still something that has been established and seen from a clinical response standpoint?
Dr. Jun Gong: The FDA approvals are really for mutations and fusions. So this K1 sub protocol, essentially, I think provides one answer that we've been all wondering about for the longest time, “Hey, could amplifications be targeted as well?” Unfortunately, we didn't include urothelial carcinomas in this study because of the FDA approval. But from a kind of a basket solid tumor perspective, I think this really dampens the enthusiasm. As of right now, it really is fusions and mutations that are targetable. Amplifications need further investigation before becoming established in solid tumors.
Dr. Rafeh Naqash: Going to the discussion with the second K2 protocol, which is mutations and fusions, can you highlight again which tumor types there where you saw some clinical outcomes that you saw and any unique insights on certain mutations or protein changes that were a little more relevant than some others?
Dr. Jun Gong: Sure. So this is the parallel study to K1, in that now we are looking at fusions and mutations of FGFR1, 2, 3, and 4. And essentially, we, again, excluded those with urothelial carcinoma, given the FDA approval for erdafitinib in this trial. The trial actually opened then the FDA approvals for the FGFR inhibitors for cholangiocarcinoma happened. So this trial didn’t really exclude those with FGFR mutated or rearranged cholangiocarcinoma as well. If you look at the breakdown of the cohort in K2, you saw a good mix of breast cancers or a couple of gynecologic malignancies. There were a couple of head and neck cancers. There were several brain tumors as well. There was one lung cancer. There were four noted intrahepatic cholangiocarcinomas. Again, we could not exclude those due to the fact that the trial had opened and was accruing when the FGFR inhibitors approved for cholangiocarcinoma happened. Similar design, with a phase II, single-arm, open-label of erdafitinib, and again, the same statistical design was implemented in that if it’s higher than 31 patients, 16% overall response rate was a primary endpoint goal. If it was less than that, it was against the 5% overall response rate.
And here in K2, 35 patients were enrolled and 25 patients were ultimately included in the primary efficacy analysis. So because it was fewer than 31 in the primary efficacy cohort, it followed the NCI-MATCH to be specified with a primary endpoint goal of 5% or higher. And here, in a heavily pre-treated cohort of more than 50% of subjects who have received prior than 3 or higher lines of therapy, overall response rate essentially confirmed was 16% with the p value of 0.034, which met the positivity cutoff of 5%. However, an additional seven patients experienced stable disease as best confirmed response. And it’s important to note that four of these were grade IV glioblastomas with prolonged progression-free survival. So ultimately, this trial was positive in reading the endpoint that outside of urothelial carcinoma, could FGFR inhibition be pursued in other tumor types that had FGFR rearrangements or fusions?
Dr. Rafeh Naqash: You mentioned glioblastoma, which is an area of huge unmet need. Do you think a trial like this as an upfront approach in glioblastoma, perhaps maybe after Temodar, could be a more meaningful way using the strongest, more precise therapy earlier on when there are certain mechanisms that inhibition of which would result in anti-tumor responses? Do you think doing this earlier on rather than second, third, fourth line would be more intriguing in some ways?
Dr. Jun Gong: I think you’ve hit upon several key points there. Firstly, just a high unmet need in glioblastomas, in general. And then to us, although it was a stable disease it was quite noticeable that four of these occurred in IDH1 and 2 wild-type brain tumors. We kind of discussed that in the discussion as well. And of these, we actually realized that in the pre-clinical and other published literatures space that for some reason, IDH1 and wild-type tended to have more FGFR alterations, while 0% were found in IDH1 and 2 mutant high grade gliomas. So I think there is something hypothesis generating coming out of this study as well even though there were stable disease. And that you may be selecting for– We may be able to have future studies to select for a specific niche of glioblastomas. And as to your point, Dr. Naqash, I think if we can have a design trial looking for these specific molecular subsets, I think it’s wide open for trials of this nature in the first line, second line, or refractory space. Even piggybacking into cholangiocarcinoma, you see, they’re now looking at these in the neoadjuvant and adjuvant space as well. So I think we can identify the subset - it’s wide open out there.
Dr. Rafeh Naqash: I completely agree. I remember my program director a few years back when immunotherapy was in the metastatic setting, it was very exciting. He gave a talk in which he said "Early, earlier, earliest," and the more early, the better it seems. So I'm guessing that it's probably something similar for precision medicine-based approaches like targeting FGFR perhaps earlier.
So what is next for some of these two studies, or these ideas that have come out of these two studies? Are you trying to develop something subsequently, or is NCI-MATCH looking at it from a certain perspective? Or what would you want to do as a next step, ideally if you had the funding and the pharma support?
Dr. Jun Gong: That’s the million dollar question. So just from the broad strokes, I think what these two back to back papers and studies comment is that amplifications may not be the more targetable of FGFR subset, but there is avenue for improvement there and further investigation. FGFR fusions and mutations however seem to go along with what we know in some of the FDA approved types now. Now the next step is in the area of precision oncology is could we expand the label indications now to other subtypes with FGFR fusions and mutations. And this is I think following precedent. You and the audience may know that there are a lot of different tumor agnostic approvals now for both immunotherapy and other targeted therapy types. So I think the goal of this study was to provide momentum for, perhaps, advancements into a tumor agnostic indication for FGFR inhibitors.
And we do cite in the K2 manuscript the results of a phase II study that was also published around the time we were writing the study up. It was the phase II RAGNAR study. And that enrolled patients, again, with FGFR fusions and mutations. And that trial was positive, too. That one was a larger study of 217 subjects. We highlight some differences in study populations as to why maybe the difference in responders were detected. Both were positive studies. It was reassuring that the overall survival impulse studies were about the same. And again, I think they don’t compete. I rather think they complement each other in providing this body of evidence that may meet- at one point, the FDA should be approached with this evidence for a tumor agnostic mutation so that more patients with this subset could be benefitting.
Dr. Rafeh Naqash: Excellent. Thank you so much, Jun.
Now, could you tell us briefly what your background is, where you’ve trained, and your interests, and how you balance clinical research with some of your personal interests?
Dr. Jun Gong: Sure. Thank you for that interest. I did my training in medical school in New York. I went to New York Medical College. And then I did my residency at Cedars-Sinai for medicine. And I went to City of Hope for fellowship where I was trained in GU by Dr. Monty Powell who maybe you folks are familiar with. And my GI training was with Dr. Fakih at City of Hope. And since then I returned back to Cedars-Sinai where I serve as a dual GI/GU focused medical oncologist. I do clinical trials in both and translational science, really focused on targeting tumor metabolism in both as well. My advice to the listeners and trainees and I tell my own fellows this, I think it’s very rare now unless you’re in phase I to do a dual focus. So I actually emphasized to my trainees that the more focused you can be, the better. Unless you are going into phase I, for example. With that, you can hone in, develop your craft. But then again, I have known several mentors who do multiple tumor types. But I think the more traditional mechanism is to focus as much as you can is my advice for the listeners.
Dr. Rafeh Naqash: Thank you again, Jun, for all those interesting scientific and personal insights. We appreciate you and working with JCO Precision Oncology for both of your manuscripts. This is the first time we have ever invited a lead author for two manuscripts at the same time. It's always good to be the first in something, and I learned a lot and hopefully, our audience would have learned a lot.
Dr. Jun Gong: Thank you, Dr. Naqash, for having me. It was a pleasure speaking with you and the crew.
Dr. Rafeh Naqash: Thank you.
Thank you for listening to JCO Precision Oncology Conversations. Don't forget to give us a rating or review, and be sure to subscribe so you never miss an episode. You can find all ASCO shows at asco.org/podcasts.
The purpose of this podcast is to educate and to inform. This is not a substitute for professional medical care and is not intended for use in the diagnosis or treatment of individual conditions.
Guests on this podcast express their own opinions, experiences, and conclusions. Guest statements on the podcast do not express the opinions of ASCO. The mention of any product, service, organization, activity, or therapy should not be construed as an ASCO endorsement.
In this JCO PO Article Insights episode, Miki Horiguchi provides a summary on the article, “TARGET: A Randomized, Noninferiority Trial of a Pretest, Patient-Driven Genetic Education Webtool Versus Genetic Counseling for Prostate Cancer Germline Testing and explains what a non-inferiority trial is.
TRANSCRIPT
Miki Horiguchi: Hello and welcome to JCO Precision Oncology Article Insights. I'm your host Miki Horiguchi, an ASCO Journal’s Editorial Fellow. Today, I'll be providing a summary of the article titled "TARGET: A Randomized Non-Inferiority Trial of a Pre-Test, Patient-Driven Genetic Education Webtool Versus Genetic Counseling for Prostate Cancer Germline Testing" by Dr. Stacy Loeb and colleagues.
To help you understand the TARGET study design, I'll first explain what a non-inferiority trial is.
One of the most common clinical trial designs we see in clinical papers is the superiority trial. A superiority trial is designed to demonstrate that a new treatment is superior to a control, such as a placebo or a standard treatment, in terms of a primary outcome that is relevant to the study's purpose. In a superiority trial, a statistical test is performed for the null hypothesis that there is no treatment difference between the two arms. If a significant p-value, which is conventionally less than 0.05 is observed, we consider that the probability that the null hypothesis being true is very low, and thus conclude that there is a treatment difference between the two arms. On the other hand, if the p-value is larger than 0.05, we cannot conclude that there is a treatment difference because the probability that the null hypothesis being true is not low enough. Here, it's very important for us to keep in mind that a non-significant p-value does not mean no difference between the two arms.
Therefore, if the study objective is to show that a new treatment has a similar treatment effect to a control treatment, the standard statistical testing approach used in a superiority trial is not appropriate. To meet this specific study objective, utilizing a non-inferiority test is more appropriate. The formulation of a hypothesis in a non-inferiority test is distinct from that in a superiority test. In essence, the null hypothesis is that the new treatment is inferior by more than the predefined margin, whereas the alternative hypothesis argues against this, suggesting that the new treatment is not inferior within this margin. A significant p-value from the non-inferiority test indicates support for the alternative hypothesis, implying that the new treatment is at least as effective as the control treatment considering the predefined margin of non-inferiority.
There are a couple of points to consider prior to designing a non-inferiority trial. The first is about the justification for using a non-inferiority study. The new treatment must offer a clear advantage other than the treatment effect, such as fewer side effects and lower cost, so that it can be a viable alternative to the control treatment as long as it maintains a certain level of treatment effect that is not inferior to the controls.
The second point is about the non-inferiority margin. The non-inferiority margin defines the threshold below which the new treatment is deemed non-inferior to the control. The selection of an appropriate margin is pivotal as it profoundly influences the power and sample size of the study, as well as the interpretation of the statistical test results. To ensure the study's objectives are met, the non-inferiority margin must be established during the study design phase. This decision should be informed by clinical expert opinions, findings from previous studies, or regulatory guidelines.
Now let me move on to the introduction of the TARGET study. The TARGET study was a multicenter, non-inferiority randomized trial to compare the effects of two types of interventions for pre-test genetic education in patients with prostate cancer. The authors developed a patient-driven, web-based education tool that consisted of nine modules with text and videos to deliver genetic testing education. They then assessed its non-inferiority to traditional genetic counseling and the decisional conflict about taking genetic testing. The primary endpoint was the change in the decisional conflict score between pre- and post-intervention. The authors estimated the difference in pre-post change of the score between the two arms and the corresponding one-sided 95% confidence interval. The non-inferiority of the web tool arm on the pre- post change of the score to the genetic counseling arm was assessed based on a pre-specified non-inferiority margin of 4. In this case, if the estimated upper confidence bound for the difference between the two arms is less than the non-inferiority margin, the study confirms the non-inferiority of the web tool to the genetic counseling in terms of the primary outcome.
The non-inferiority margin for this study was determined based on a previously conducted similar study. For the TARGET study, several factors underscore the appropriateness of using a non-inferiority trial. First, the web-based education model is likely to significantly increase convenience compared to traditional genetic counseling, which is delivered in person or through telehealth appointments with the genetic counselor. The introduction of the proposed web tool is expected to reduce logistical burdens for patients, such as those related to transportation and scheduling. Second, from the perspective of healthcare providers, the adoption of the proposed web tool could reduce the workload of genetic counselors, offering a potential solution for a shortage of counselors.
A total of 346 patients were randomly assigned in a 1:1 allocation to either of the two interventions. The primary analysis population was the modified intention-to-treat population, which included 153 on the web tool arm and 162 on the genetic counseling arm. The estimated difference in pre- post-change of the decisional conflict score between the two arms was -0.04 and the upper boundary of the corresponding confidence interval was 2.54, which was less than the predefined non-inferiority margin. The p-value for the non-inferiority test was 0.01. The authors reported results for the secondary endpoints, which included cancer genetics knowledge, attitude toward genetic testing, and satisfaction with genetic counseling. It was also reported that a total of 265 patients took genetic testing, and among the total, pathogenic variants were identified in 42 patients. The authors concluded that the study results support the use of a patient-driven web tool for expanding access to pre-test education for germline genetic testing among patients with prostate cancer. The authors also mentioned some limitations of this study, one of which is the limited racial and ethnic diversity among the study population. Some requirements to access the web-based tool, such as a computer and Wi-Fi access, may raise concerns about widening disparities in access to genetic services for cancer patients. Further studies to examine ways to address these limitations are needed.
Thank you for listening to JCO Precision Oncology Article Insights, and please tune in for the next topic. Don't forget to give us a rating or review and be sure to subscribe so you never miss an episode. You can find all the ASCO shows at asco.org/podcast.
The purpose of this podcast is to educate and to inform. This is not a substitute for professional medical care and is not intended for use in the diagnosis or treatment of individual conditions.
Guests on this podcast express their own opinions, experience, and conclusions. Guest statements on the podcast do not express the opinions of ASCO. The mention of any product, service, organization, activity, or therapy should not be construed as an ASCO endorsement.
JCO PO author Dr. Christian Rolfo shares insights into his JCO PO article, “Liquid Biopsy of Lung Cancer Before Pathological Diagnosis Is Associated With Shorter Time to Treatment.” Host Dr. Rafeh Naqash and Dr. Rolfo discuss how early liquid biopsy in aNSCLC in parallel with path dx is associated with shorter time to treatment.
TRANSCRIPT
Dr. Rafeh Naqash: Hello and welcome to JCO Precision Oncology Conversations, where we bring you engaging conversations with authors of clinically relevant and highly significant JCOPO articles. I'm your host, Dr. Rafeh Naqash, Social Media Editor for JCO Precision Oncology and Assistant Professor at the Stephenson Cancer Center, University of Oklahoma.
Today we are thrilled to be joined by Dr. Christian Rolfo, Associate Director of Clinical Research at the Center of Thoracic Oncology at the Tisch Cancer Institute at Mount Sinai Health System. He is also the lead author of the JCO Precision Oncology article entitled "Liquid Biopsy of Lung Cancer Before Pathological Diagnosis is Associated with Shorter Time to Treatment."
Our guest's disclosures will be linked in the transcript.
Christian, it's great to have you here. Welcome to our podcast and we are excited to learn about some of the interesting results from your study.
Dr. Christian Rolfo: Thank you very much, Rafeh. It's a pleasure to be here and discuss about liquid biopsy.
Dr. Rafeh Naqash: You have a very important role in different liquid biopsy consortiums. This is an initiative that you have been leading and spearheading for quite a while, and it's nice to see that it is becoming something of a phenomenon now on a global scale where liquid biopsies are being implemented more and more in earlier stages, especially. For the sake of our audience, which revolves around academic oncologists, community oncologists, trainees, and patient advocates or patients themselves, could you tell us a little bit about the background of what liquid biopsies are? And currently, how do we utilize them in the management of lung cancer or cancers in general?
Dr. Christian Rolfo: Liquid biopsy has been gaining importance over the years. We started to talk about liquid biopsy in 2009 when we started to see some correlations with EGFR mutations. In practicality, what we are doing is the most common or most applicable indication is to go for liquid biopsies from the blood, peripheral blood. So we are doing a blood draw and from there, what we are capturing is the DNA or fragments of DNA that are still in circulation. But the liquid biopsy definition is a little bit more broad and we can apply the concept of a minimally invasive approach to different fluids of the body, including pleural effusion, urine, and including CSF that is another indication, there, we are going to be a little bit more invasive than peripheral blood, but it is also an emerging tool that we will have to find specific indicators. In cancer, we started the history of liquid biopsy in advanced disease with the identification of biomarkers, and then from there, we are moving to other scenarios, including, nowadays, monitoring minimal residual disease and early detection. And that is applicable also for other tumors.
Dr. Rafeh Naqash: Thank you, Christian, for that summary. Now, as you've rightly pointed out, we have come to implement liquid biopsies more and more, both in the academic setting and the community setting. And this has definitely led to faster turnaround time in some ways compared to tissue. In this study that you have authored with the help of many other collaborators and Foundation Medicine Flatiron Health data, the goal here, from what I understand, was to look at liquid biopsies that were done before, resulted before the pathological diagnosis. Could you tell us a little bit more about the premise of this study, why you thought about this question and how did you try to implement that idea to get to some of the interesting results that you see here?
Dr. Christian Rolfo: Yeah, so what we are seeing generally in lung cancer and also in people with other tumors is that patients are having a journey and that they start seeing different doctors until they get a diagnosis. Generally, after the pathological diagnosis, if you don’t have an in-house technology that is doing reflex testing, generally, oncologists need to request for testing and that is taking time. So if we are looking for comprehensive days until a patients are able to get a molecular profiling before we start the treatment is sometimes very long. We are talking, in some cases, about months. So, how we can speed the process, that was the main question. We tried to include liquid biopsy in the staging procedures that we generally were doing when we have a clinical diagnosis of lung cancer. It’s either images that we are used to do, PET scans, MRIs, and other assessments, we want to include liquid biopsy there before the biopsy. And that's what we did. We were searching for this specific aim using the Flatiron Health Foundation Medicine electronic health records from 280 centers across the United States. We included a big number of patients in this analysis, more than 1000 patients for the first analysis.
Dr. Rafeh Naqash: That's phenomenal that you had real-world data from 200+ centers across the US. Of course, when you have patients on a clinical trial versus patients in the real-world, we all know that there are differences in terms of approaching, overseeing, and managing these individuals. So this data set is an extension of what we could see in the real-world setting.
Could you tell us a little bit about the number of patients that you eventually identified that had liquid biopsies done before pathological diagnosis? I think you have different cohorts here, a group that was before and a group that was after, and you compared several important metrics treatment-wise from what I see. Could you highlight those for our listeners?
Dr. Christian Rolfo: Yeah. So we were looking for patients who had a liquid biopsy CGP, comprehensive genomic profiling, ordered within 30 days pre diagnosis and post diagnosis. We focused on 5.2% of patients, which corresponded to 56 patients who ordered a liquid biopsy before diagnosis. The median time was eight days between the order and diagnosis and the range was between 1 to 28 days. And that was compared with 1020 patients who ordered a liquid biopsy after diagnosis. It is important to be clear that both cohorts had a similar stage and ctDNA tumor fraction. We can explain later what tumor fraction is, because it was done in addition with a paper that we just published last week. Liquid biopsy patients were consulted to have this CGP median one day after diagnosis, versus 25 days after for patients who had their diagnosis and their liquid biopsy later on. So, from these patients, the majority of the patients, 43% of LBx-Dx were positive for an National Comprehensive Cancer Network driver, and 32% had ctDNA TF >1% but were driver negative, so that is what we call presumed true negative. From here, maybe I can explain what is tumor fraction and, in general, how we use it.
Dr. Rafeh Naqash: I think that would be great for our listeners. We see this often in more and more liquid biopsy results nowadays, and I've tried to explain it to some of my fellows also. So, it would be nice if you explain for the sake of our listeners what tumor fraction is, what does it mean clinically, can you use it in a certain way, what biological relevance does it have.
Dr. Christian Rolfo: So we are analyzing another paper that came out this week in cancer research on the concept of tumor fraction and it’s a new definition. So what we are doing with tumor fraction is an algorithmic calculation or mathematical calculation on the amount of DNA of the cells also taking into consideration the math, the quantity of DNA present in the sample. So we are going very low in the sensitivity of this analysis and capturing there the real informative results of the ctDNA of the liquid biopsy. So in practicality, when you see a report that says the threshold that was established in this study was more than 1% or less than 1%, so patients who have a tumor fraction of more than 1%, we can really consider this liquid biopsy informative. And also in this next publication, we compared with tissue. In patients with a tumor fraction of more than 1%, were completely 100% correspondent with what we found in the reflected tumor tissue, the NGS. But what happened in patients with a tumor fraction of less than 1%, we can say that these patients are not informative. So we need to wait for the tissue biopsy result to come in because we were able to recuperate several patients that the liquid biopsy was negative with the tissue biopsy positive.
This is an important concept because we are distinguishing not only the informativeness of liquid biopsy, but also we can distinguish between patients who are considered not shedder based on what is considered a shedder. And that was a problem until this kind of introduction was a problem before with the technology because the technology wasn't very fast to distinguish the sensitivity or high sensitivity. Now, the sensitivity is no longer a problem. Maybe, there is really value of information in what we have in liquid biopsy, and using this mathematical help, we can get these patients distinguished and help more people. So that would be really interesting.
Dr. Rafeh Naqash: You touched on a few important concepts here, and one question I have, and I think there's no better person to answer this question. You're the right person to answer this question for our audience. Do you think when you have a liquid biopsy tumor fraction of less than 1%, and you have a tissue that is pending with an NGS, where tissue NGS has not resulted yet, but liquid biopsy results come in and tumor fraction is less than 1%. But let's say you have a non-smoker with a typical driver mutation and clinical characteristic positive individual in the clinic, and the tumor fraction is less than 1%. How much can you trust that liquid biopsy when the tumor fraction is less than 1%. Because do you think some of these driver mutations, like you mentioned, could be low shedders and you could miss a potentially actionable mutation on a liquid biopsy if the tumor fraction is less than 1%? Is that something that you've looked at or correlated or understood what would be the clinical meaning of that?
Dr. Christian Rolfo: Absolutely. So there are two concepts here. A liquid biopsy could be non-informative, and that is what we saw in this paper. So you have patients that have a liquid biopsy negative, and that we see in the clinic, a liquid biopsy negative tissue biopsy positive. That could be because the liquid biopsy is not informative, but it could be also that the patient, for some biological reason, and we don't have an answer about that, they are not shedding the ctDNA in the bloodstream, ctDNA that we can capture. What we saw in different studies, including one of the papers that we presented also in ASCO last year with a MET amplification and METex14, for example. In the study that was the VISION study using tepotinib, you see that patients who have a liquid biopsy negative are doing a better outcome compared to a patient who have a liquid biopsy positive. So I believe that we still have patients who are not shedders for some biological reason, that could be put in together with patients who have more bone metastasis than organ metastasis, or patients who have more in location, for example in the brain. These patients are difficult to capture in ctDNA due to some biological reasons. But also you have patients who are non-shedders. For the technicality of the parts of this tumor fraction analysis, it is really important to distinguish that and we will hear more and more. So, as you say, we have already some reports in some companies like Foundation are doing, but some others like to incorporate this tumor fraction. And several in-house technologies allow also to have this kind of mathematical calculation. So that is what we are facing now, to really understand better the power of liquid biopsy.
Dr. Rafeh Naqash: Now, some of the other things that your project or paper that you published with JCO PO does not necessarily cover is the payer aspect of this. Now, we've had more and more discussions, obviously, and more and more information has been highlighted with the payers that this is an important test and needs to be reimbursed, even though if you do tissue NGS, liquid biopsies are complementary to tissue. So taking both together is probably a better view of the overall tumor or the mutational status of the tumor. But one of the biggest holes in this whole process, and this is my personal experience, I want to know what you think, is that we can't order these tests when the patient is admitted to the hospital, and 50% or more patients end up getting diagnosed in the hospital during an inpatient stay. The average hospitalization for someone with lung cancer is five to seven days on average, and then another one to two weeks to get into the clinic to see an oncologist. So what would your thoughts be there? How can we improve things there in terms of, can we try to do something different so that the payers agree that, yes, you can send a liquid biopsy when the patient is admitted, because there's that 14-day Medicare rule? Has your team, or have you in particular, tried to navigate some of those issues, and what are your thoughts on how we can try to improve some of those conversations?
Dr. Christian Rolfo: Yeah, that's a really good question, because here we are talking about inequities in access to the technology and the results and it's crucial. Several of our patients, specifically in lung cancer, they are coming to our consultations or to the emergency with a very bad situation so they need to be admitted immediately. And as you say, they can be there for one month waiting for results or for recovery or for stabilization of their general condition before we can start. Several of these patients will have some biomarkers that we can target with treatment. So in other words, I will say that this is a stupid rule because we cannot have in 2024 these kinds of limitations to access to treatment when we have on one side, the FDA is doing a terrific job to get drugs approved in a very short time, and on the other side we have payers who are not understanding the concept of molecular or precision oncology.
So what we are trying to do in these cases, to be honest, is to navigate with the vendors and try to get this done. I generally send the samples because I consider that personally that it is a very crucial information. And in several cases, we have started targeted therapies while the patient is still admitted. So I think it's something that we need to put in a better effort, because already we are not doing enough for our patients, if you look at the data of the MYLUNG Consortium that was presented in ASCO some years ago on the testing performance in the community practice, 50% of the patients with lung cancer were tested there were only some in minority groups, African Americans, 39%. So I think we need to do better in education, but also from the payer side, it's really crucial that they understand this concept.
Advocacy groups have a lot of say here. They are also doing an important job on that. We are now launching with ISLC, ISLB, Lung Cancer Europe, and Longevity in a survey that is to make also the patients aware what is the importance of molecular profiling, tissue or liquid biopsy, it’s very important that you get something to treat the patient and select the right treatment. And even to say, there’ll be a whole other work in your case so that is really important.
Dr. Rafeh Naqash: Absolutely, I completely agree. We have made a lot of strides, but there is still a lot of room for improvement in terms of equity, access, and reimbursement.
Now, one of the things that I noticed in your paper, and you could tell me a little bit more about this, when you looked at the pre-diagnosed liquid biopsies, meaning before tissue diagnosis, 56 individuals there suspected to have lung cancer, community-based testing was identified in 53 individuals versus academic being three. This is very encouraging when you see something like this happening in the community. Did you look at that? Did you try to understand why or how that was the case? Because in a general community setting, I would think that community practices have a more complicated system of reimbursement because they are dependent on direct reimbursement, whereas in bigger academic centers, there’s some leeway here and there. So did you try to understand how they were able to order this before tissue, could you give us some insights there?
Dr. Christian Rolfo: Yes, I think it was not big in this specific question, but it's a very interesting topic. Because we, generally, in academia, will believe that we are doing the things in advance and we are more, compared with the practical and the general practitioners or the general colleagues in the community practice, we have more resources. But sometimes, and it's true, obviously, we have more resources in terms of research and more opportunities in terms of clinical trials in some cases. But I think we understood with this minimal example that there is an important interest among general oncologists in the community practice to get this done. And this is something we need to emphasize, because sometimes we are putting the blame on our colleagues that are outside the academic centers on this lack of testing, and it’s not really true sometimes. So this is a good point to start to work together and try to get more things done for our patients and try to get also the reality.
I think one of the problems we will have in the future that we can face right now is the lack of new figures in this molecular profiling. I am referring, for example, molecular nurses or personnel that is working and helping to get this done. We need to have more people that are working in this education for the patients in the access to treatment and access to the technology, but also to navigate better these problems with payers that sometimes in some patients that seem to be overwhelming. Because when you talk about the $100 that could be extra, it’s hard for some patients. So we need to be very conscious about that. So having a new figure in the hospitals and the community practices could help to test more patients.
Dr. Rafeh Naqash: And I think at the end of the day, the payers or the reimbursement mechanisms need to understand that genomics is part of the diagnosis these days. It's not ancillary, it’s not an addition, but it is part of the diagnosis. I'm pretty sure you have had similar instances where you get a confusing pathology result but then a genomic result points in a certain direction. You treat the patient in that direction, and then you see the patient benefiting in the tumor shrinking, which suggests that genomics is complementary to the path diagnosis. It’s not necessarily a surrogate.You can’t replace pathological diagnosis, but you can use genomics as a complementary diagnosis as part of the whole paradigm of treating the entire patient. So I think we definitely need more and more conversations like the ones that you’re having or your liquid biopsy consortium is having and then more education from the FDA. Of course, more legislation, more advocacy.
Going back to the paper, I did notice another interesting thing, which is, again, very encouraging is patients with lung cancer with a performance status of 2 or about had a decent proportion of testing done. Which, again, points out to the important concept of avoiding these preconceived biases that, “Hey. If somebody is not a great performance status, testing and finding something in that individual could potentially change a lot for the individual.” Do you have any personal examples from patients you have treated or seen in the clinic for our listeners where you identified something and maybe they were not doing as great initially, and then you identified something in liquid biopsy, treated them and it changed the entire course of their illness and whole trajectory for them?
Dr. Christian Rolfo: Being working in lung cancer for years, everyone has this kind of patient that we see that their performance state was very bad. Obviously, as a clinician, we need to identify why the performance is bad and is deteriorating. So we see some patients in lung cancer, some of them, they can have a very important comorbidity packet that is associated with lung cancer. So in patients who have a deterioration for lung cancer, and we find a driver help in some patients that were doing a kind of a weakness, and that is something that we see in several patients, specifically in patients living with leptomeningeal disease. In some cases, when we start to do drivers that have a big impact in the crossing the blood-brain barrier, I have a good response. I have patients that had an important recovery. So this is something we need to distinguish and sometimes when the patients seem very bad they say, “Okay, we go directly to targeted care or supportive care.” We try to test these patients as well because these patients have an important impact on the quality of life that we are treating. We will not be able to cure patients in this setting with targeted therapies, but we can certainly make an impact in the quality of life and also in our form of survival.
Dr. Rafeh Naqash: One of the other questions that comes up often when you’re in a multi display team, since most cancers these days are on the multi display decision making opportunities to treat the patient the best possible way is: Who orders the liquid biopsy? I remember from my fellowship several years back, our program director Paul Walker, who is, again, an amazing lung cancer thoracic oncologist, he had advocated that our endoscopic suite folks, the bronchoscopist, whether it was pulmonary, interventional pulmonology or CT surgeons, whoever did the bronchoscopy for the first time in the patient that they would send it whenever they see the patient from the bronchs. This was around six, seven years back. And I think Paul was a little ahead of his time and I didn’t necessarily understand the implications that this would have.
And now, as I progress in my own little career, I can see the vision that he had, which I think a lot of other sectors have tried to do, and I’m pretty sure you have a certain process, too. Is that something we should try to talk more and more about? Because, of course, when you do the bronch, then you get a diagnosis and the patient sees the oncologist. This whole process takes anywhere from two to three weeks, maybe even more for smaller centers. So, is that something that you’re doing or you see that you’re having more conversations that, “Hey. Whoever sees the patient first should be able to order the liquid biopsy.” It's not necessarily the medical oncologists, it doesn’t mean I love to order sequencing results or sequential tests, but it could cause a delay in the patient care. So, could you tell us a little bit more of that?
Dr. Christian Rolfo: So it's really important, this part, because we need to create in our institution flows that will have this very well organized. And ideally, in the ideal world will be that we have reflex tests coming from the pathologist, but it's not happened in several places, because we don't have our NGS at home, or we are sending to vendors, and sometimes we are not sending to them. So that is one of the aspects.
The second aspect, and that I think is still a problem in some treatment, is that we still have 24:30 cytologists coming out in place of covariances. And in our institution, we were working very hard with our interventional pulmonologists and interventional radiologists to get this quality of tissue appropriate, and we have a very good rate of success and issues in a very minimal quantity of patients. Obviously, some patients are very difficult to get samples, and we need to refer still with cytology. But in some cases, where our surgeons or our pulmonologists have sent in samples for NGS, and I think this is we are coordinating. “I will see this patient next week. Can you please start to order?” And here, our nurse practitioner, our nurses in the team are also playing an important role for the reason I insist in the idea to have new figures that could be these molecular navigators we can call, or molecular nurses that helping coordinate this, not only the coordination, but also in the discussion of molecular tumor boards. We did an experience like that some years ago at Maryland University, and actually it was a very important opportunity to decrease the number of quantities of issues and get the results done very quickly. So I think it's important to come to have conversations with our colleagues, pulmonologists, radiation radiologists, interventional radiologists, pulmonologists and pathologists to get this done very quickly.
Dr. Rafeh Naqash: I love the idea of molecular navigators. And of course, everybody in the current day and age, we’re having staffing issues, so getting a molecular navigator would be awesome, but I’m not necessarily sure how everybody would be able to implement it. But I think in the bigger picture, whether it’s molecular navigators or multi disciplinary nurse navigators in general, liaisons in general, I think we all can do a better job in trying to coordinate some of these testings. And we have tried to do that through our thoracic oncology group and of course, there’s a lot of progress that needs to be made, one step at a time.
Dr. Christian Rolfo: If somebody is interested in this topic on the International Society of Liquid Biopsy, we started with a project that is called a Certificate for Advanced Studies in Precision Oncology. So we are educating the healthcare team for all this process and trying to get practical insights to have this career later. Because I think it will be something that’s interesting for nurses or pharmacists to get this kind of career later or get another approach in their career.
Dr. Rafeh Naqash: Thank you so much, Christian.
Now, going to not the scientific part, which I think is the most interesting part of this conversation is to talk about you and your personal journey. Could you tell us a little bit about where you started, what your career has been like, how did you progress? Because you have a lot of junior faculty that listen to this and it's always good to take inspiration from people like yourself.
Dr. Christian Rolfo: Thank you. As you can hear my accent, it’s not from here. So I was born in Argentina, I did my medical degree there. And then I had the opportunity to get a scholarship in Italy. I went to Italy and I stayed there for seven years. I did my fellowship there again, and I started to know there precision oncologists. My journey started in sarcoma. And actually I was working in the group of Dr. Casali's group, a very well known sarcoma expert. And at that time we were running phase I trials for imatinib, I remember, known as GIST. I saw this kind of response and awakening of patients that were really in very bad condition, with only through this imatinib. Very little to treat that disease at that moment, a median overall survival of two months. So I started to be interested in that. Then I moved from there to Spain and met Dr. Rafael Rossell, who was my mentor. In Italy, I have also a mentor in breast cancer, Dr. Luca Gianni, one of the pioneers in breast cancer treatment. So knowing all these people and having the support of them, was really crucial.
So I think this is the first advice for junior faculty: try to choose your mentor, even if your mentor is not in your center. Like the case, for example, Rafael Rossell was not in my hospital, but he was my mentor. So having this kind of discussion, I did my PhD in EGFR mutation, at that time was the fashion, not immunotherapy, of the moment. And then from there, after eight years in Spain, I moved to Belgium. I have a short period of completing my training at MD Anderson and I went to Belgium to Antwerp University and that was the opportunity to become the Director of the phase I program in the Early Clinical Trials Unit. It was really exciting to see growing a unit, and now they continue at the center in Belgium. My colleagues that stayed there, they are doing a terrific job of continuing this idea. And from there I went to Baltimore, three years working at Maryland University being the Director of Thoracic Oncology and early clinical trials as well. Three years after, I moved to New York, and here doing this journey in clinical research, also being the Director of Clinical Research at the Center for Thoracic Oncology.
Life has put me in different places, different cultures, different opportunities. For me it was a really good journey to be in different countries, knowing different ways to see oncology as well, and immediately to work, because it was a shock coming from Belgium to the area of Baltimore where I had the reality to discuss peer to peer conversations and things that are not usually discussed in Europe. So it was really a very nice journey to learn, to have the capacity to adapt.
That is the other thing, my second advice, if I can give advice, but if you have the opportunity to go to some place, adaptation is the most important. So try to enjoy what you’re doing and try to enjoy and learn from the patients, hopefully, and contribute your knowledge as well.
Dr. Rafeh Naqash: Thank you so much, Christian. Two last questions. For all the places that you visited, what is your favorite place? And what is your favorite food?
Dr. Christian Rolfo: My favorite place to live, I have Italy in my heart. Obviously, Argentina is my place, family. But Italy is in my heart. And then Spain, Spain gave me my wife and my son. So I have very good memories there and it’s a very nice place. Obviously, I’m Argentinian, so for me it means meat in some places, Asado, that is a typical Argentinean one. But also, I am very eager to enjoy the pasta and paella, so we have several things. Anyway, here in New York, the pizza of New York is great. It is not Italian. This new way to make pizza from New York is fantastic.
Dr. Rafeh Naqash: I can try to see you’re trying to keep everybody happy in a politically correct way.
Dr. Christian Rolfo: I didn't mention Belgium, but we have chocolates there.
Dr. Rafeh Naqash: That is true. Every place is special and unique in different ways.
Christian, thank you so much. This was very entertaining and very informative for me and hopefully for the audience. Thank you so much for being a part of this conversation. And thank you so much for submitting your work to JCO PO. We hope you consider JCO PO for future research in this exciting area as well.
Dr. Christian Rolfo: Thank you. Thank you very much, Rafeh, for the opportunity. And JCO Precision Oncology is a really great forum to discuss precision medicine. Congratulations for all your work. The last, if you allow me to give an advertisement here. We have our Liquid Biopsy Congress, the ISLB, the annual conference will be in Denver from 20 to 25 November, so just before Thanksgiving day. So if you are able to go there, we will have a lot of discussion on liquid biopsy like we did today. Thank you very much.
Dr. Rafeh Naqash: Thank you so much for highlighting that, and hopefully, our listeners will try to register and be part of that meeting.
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