SIRT for Nonresectable CRC With Liver Metastases - Episode 5

Perspective on the Future Management of mCRC

October 31, 2018

Michael Cusnir, MD:The way this data may affect the treatment selection for us, as clinicians, is that it’s much more likely, nowadays, if I’m seeing a patient with a right-sided tumor—and mostly if they have liver-limited metastatic disease that is nonresectable—that I might move my selective internal radiation therapy up with frontline therapy.

It should be noted that the way we treat the right side of the colon has been a challenge, but that should not negate the benefit we have seen with the use of selective internal radiation as treatment for both sides of the colon in subsequent lines of therapy. What this will affect in the frontline setting is that I will move my selective internal radiation therapy to the earlier lines and reserve my selective internal radiation for subsequent lines or even maintenance therapy. This study was done only as a frontline study.

Now, again, I do have my criticisms on the study. I would have liked to have seen liver-only disease, not liver-predominant disease. But the overall survival that we have seen in the unselected population on the right side of the colon is surprising, and it’s something we should be able to build upon.

I think this data will change clinical care. We would like to get our mutational analyses, our next-generation sequencing, and all of that as soon as possible, when we get a patient with metastatic colorectal cancer. I have the feeling that we, as clinicians, are going to be referring patients with liver-only right-sided tumors to our interventional radiologists almost at that same time as we’re waiting for our molecular studies. These patients should be evaluated quite early in the disease and should be able to get started on treatment, then move on to selective internal radiation therapy very early in the disease.

I have the feeling that we’re going to learn much more over the next year or 2 about the amount of effectiveness that selective internal radiation therapy has on the immune level of the patients who have right-sided tumors.

What we have seen is that the right-sided tumors are mostly what we call immune tumors. It’s going to change the paradigm of practice dramatically. We’re hoping to see more studies of combinations of these treatments and of selective internal radiation with immunotherapy. This is probably going to be something that will change the way we manage our patients in frontline metastatic colorectal cancer.

Transcript edited for clarity.