An Argument Against Radiation Therapy for Borderline Resectable Pancreas Cancer

Lisa Kachnic, MD, Irving Comprehensive Cancer Center at Columbia University, New York, NY, discusses the debate she participated in at the 2023 Great Debates and Updates in Gastrointestinal Malignancies meeting, on the use of radiation therapy for patients with borderline resectable pancreas cancer. Dr Kachnic presented that case against using radiation therapy in this setting.

Transcript:

Hi, I'm Lisa Kachnic. I am chair and professor of the Department of Radiation Oncology at Columbia University in New York City. I'm very excited to be here at the Great Debates and Updates in Gastrointestinal Malignancies meeting, discussing the “no” side of a debate on whether we should use radiation therapy for borderline resectable pancreas cancer.

In our case, it was borderline resectable, which was chosen because this is when the cancer is up against the vessels and it's very hard for the surgeon to take out. There’s an opportunity to give neoadjuvant treatment, and that could be chemotherapy or chemotherapy plus or minus radiation. And my argument was that we have absolutely no evidence from randomized trials for either giving radiation in a long course, which is over 5 weeks, slow and steady with chemotherapy, or doing radiation alone in very large doses, typically over 5 treatments or fractions, as we call them in radiation oncology.

The trials that we have just do not show any survival signal or benefit over giving chemotherapy neoadjuvantly before surgery. Why is that important? Because pancreas cancer, the only cure is with surgery and unfortunately, only a small percentage of patients actually are able to undergo surgery upon presentation. Pancreas cancer also is a systemic disease. Most of the patients end up having disease spread over time. To make the borderline resectable cancer come out with a surgeon, we need help in shrinking the disease off the vessels. That's where radiation, we thought, would have a big bang for its buck, especially with these high doses. But evidence has shown this not to be the case.

I think the highlight of our debate was reviewing some of the newer techniques of radiation therapy. Again, giving these high doses, usually 5 treatments. It really takes a skilled team and also skilled equipment, much like a surgeon. And perhaps we haven't had the right studies to evaluate that right now. We’re hoping working together with newer studies with this more modern radiation approach may show a select group of patients that could still benefit from radiation therapy.

My learning on this debate was that I actually do use stereotactic body radiation therapy after chemotherapy for patients with borderline resectable pancreas cancer. But going through the data sets, there seems to be no evidence to support my actual practice. I think what our center and many others are trying to do is understand which patients may still have a role for radiation in this setting. It's probably us understanding more the genomic signature and the molecular underpinnings of what radiation in these high doses may be doing and how it should be sequenced and in what combination of chemotherapy or immunotherapy or maybe new agents we don't even know about yet. Again, I hope the work that collaboratively we do together in the US and even internationally may help us answer that question.

Source:

Kachnic, L. “Debate: Is There A Role for Radiation Therapy in Borderline-Resectable Pancreatic Cancer? Yes vs No — No.” Presented at the Great Debates and Updates in Gastrointestinal Malignancies; March 30-April 1, 2023; Chicago, IL.