Future Implications of ctDNA in the Management of NSCLC

Future Implications of ctDNA in the Management of NSCLC

Mark G. Kris, MD, FASCO: When we have a patient that had surgery, or chemotherapy and radiation that eradicated or cancer and under monitoring have the return of ctDNA, that's a sign that it's likely the cancer has returned in their body. So, it gives you a kind of a heads up to do whatever necessary testing to prove that, or at the very least monitor them more closely. And if indeed you do detect cancer, at that point on an imaging study, then you could intervene quicker and hopefully lead to a better outcome for the patient. I mean, that's the hope as we move forward.

I think in the short term, the ctDNA will be used in addition to CT scan monitoring. As time goes on though and depending on how precise we can make the testing of the ctDNA, it could be possible that we would only follow patients by ctDNA. It has the potential to be more sensitive to find answers when they're tinier to find cancers at the earliest possible time. And it's theoretically possible that someday we'd be following people by looking at their ctDNA. The nice thing in the surgical patients is we have their tumor; we know exactly the nature of their tumor to go look for that. But times going to tell if we can do that. But I think now, we're going to use them together to give us the most information we can about a patient.

I think we need some consensus as to what is the best test. And when the timing of the of the tests and we're not there yet. We also need a greater experience of the ASCO abstracts that we are discussing today had, you know, dozens or maybe 100 patients, not 1000s of patients, we really need some more experience before we can say that this is going to be a standard of care. But what we can say from these abstracts is there's a lot of potential there and it just needs to be worked out.

I think the first thing that's going to happen is more interrogation of like the definitely the tumors removed at the time of surgery, to estimate your risk of recurrence, looking at the pathologic specimen and seeing how effectively the new adjuvant treatment worked. Also using artificial intelligence techniques to look at tumor tissues into and to learn from the experience of prior patients which characteristics could predict return, I think that is going to be another piece of the puzzle. And it may be that using the ctDNA with that information about how effective that particularly neoadjuvant treatment was, that becomes an even better way of monitoring the patient and a better way of estimating who needs an adjuvant therapy or not. So, I think also technologies, it's going to get better, it'll get faster, it'll get more precise and it's going to be more widely available.