Welcome to Closing the Gaps in Non-Small Cell Lung Cancer on ReachMD, sponsored by Lilly. Joining us today from the University of Pennsylvania’s Perelman School of Medicine is medical oncologist and assistant professor Dr. Joshua Bauml, who discusses treating patients with RET fusion. Let’s hear from him now.
When a patient presents with non-small cell lung cancer or papillary thyroid cancer, with the recent approvals, one question that comes up is: Could this patient have a RET fusion? We know that the drugs pralsetinib and selpercatinib have substantial activity against RET fusion-positive disease with selpercatinib recently gaining FDA approval in this space. So, how do you know if your patient has one of these? In my opinion, the best approach for identifying a RET fusion is using an RNA-based fusion assay. This is the RNA equivalent of a next-generation sequencing platform. One of the barriers of using DNA-based next-generation sequencing is that the recurrent introns that are present in many fusions can make identifications of translocations or fusions complex, and so this RNA approach sort of overcomes that barrier. So, that is my preferred method, though there are other ways of looking for RET fusion. You could do FISH, and you can identify them on DNA-based assays, but as I said, the sensitivity is lower.
When I see one of these alterations, how do I approach such a patient? Well, in non-small cell lung cancer, to me the answer is relatively clear. I would give them a drug like selpercatinib in the first-line. And the reason that I would use that over immunotherapy is that we have seen in multiple series that patients with a molecular driver alteration tend not to benefit as well from immunotherapy as other patients with lung cancer. Based upon a series that was done out of MD Anderson where they looked at their patients with RET translocation and compared outcomes for those receiving immunotherapy and those receiving targeted therapy on a clinical trial, they found that those receiving immunotherapy did much worse in terms of progression-free survival, and so that really supported my approach of using targeted therapy first.
That was Dr. Joshua Bauml sharing approaches to identifying and treating non-small cell lung cancer patients with RET fusion. To revisit any part of this discussion and to access other episodes in this series, visit ReachMD.com/NSCLC, where you can Be Part of the Knowledge. Thank you for listening!