Dr. Anil Vachani, assistant professor of medicine, and director of clinical research in interventional pulmonary services, at the University of Pennsylvania Health System, joins host Dr. Lee Freedman. They talk about Dr. Vachani's exciting work on the development of a blood test that may be useful in distinguishing benign from malignant in patients with lung nodules. Along with researchers at the Wistar Institute in Philadelphia, Dr. Vachani has developed a test utilizing the profiling of gene expression of peripheral blood lymphocyte involved in tumor immunity. Still in the early stages of development, this work has led to a 24 gene 'signature' that has a sensitivity of 85 percent and specificity of 87 percent. Find out how soon this test might be available for clinical use, and other potential applications of this technology in clinical medicine.