In a special cobranded episode between Oncology On the Go, hosted by CancerNetwork®, and the American Society for Transplantation and Cellular Therapy (ASTCT)’s program ASTCT Talks, host Rahul Banerjee, MD, FACP, spoke with colleague Hitomi Hosoya, MD, PhD, about a study she and coauthors published in Blood. In their study, Hosoya and colleagues assessed the underlying mechanisms of CAR T-cell–related lymphomas developing in the gastrointestinal tract. The study focused on a particular case involving a 50-year-old patient with relapsed/refractory multiple myeloma who developed T-cell lymphoma after receiving cellular therapy in the seventh-line setting. 

The discussion began with an overview of the patient’s treatment course, who initially responded well to seventh-line CAR T-cell therapy and experienced grade 1 cytokine release syndrome with no neurotoxicity. Two months after initiating this line of therapy, the patient experienced diarrhea and subsequent hospitalization. Following multiple endoscopies and the use of steroids and other biologic agents, the patient’s diarrhea persisted, which resulted in notable weight loss and cachexia. A biopsy revealed that the patient had developed T cell infiltration in the small intestine, which correlated with an eventual diagnosis of T-cell lymphoma. 

After the patient’s diagnosis, Hosoya outlined her team’s decision to administer cyclosporine to help mitigate and eventually resolve the patient’s diarrhea. Beyond this symptom management, she highlighted the challenges of treating those with GI-related T-cell lymphomas based on a lack of sufficient treatment protocols and clinical experience across the country. Overall, she emphasized teamwork as an essential component of managing and further understanding CAR T-cell lymphomagenesis.

Banerjee is an assistant professor in the Clinical Research Division at the Fred Hutchinson Cancer Center and a member of the ASTCT Content Committee. Hosoya is a principal investigator in Hematology & Cellular Therapy at Cedars-Sinai Medical Center and an instructor of Blood and Marrow Transplant and Cellular Therapy at Stanford University.

Reference

Hosoya H, Bastidas Torres AN, Fernandez-Pol S, et al. Long-term follow-up of gastrointestinal CAR T-cell lymphoma: homing, clonal expansion, and response to cyclosporine. Blood. 2026;147(11):1191-1198. doi:10.1182/blood.2025031423