Evolving Treatment Paradigms for Renal Cell Carcinoma - Episode 9

Disease Progression in Patients with Metastatic RCC


Daniel George, MD: This section is going to focus now on the sequencing approaches for relapsed and metastatic renal cell carcinoma. And I think whenever we discuss switching from frontline therapy to subsequent therapy, we have to start with how we’re defining disease progression. So, Walt, outside of RESIST, which is used in our clinical trials, in your practice, how do you define disease progression?

Walter Stadler, MD: So, I think you have to look at the CT scans, right? That, especially with the variability in radiology reports, it is not just the bottom line that says progression, it is, what does this look like, not only compared with the immediately previous CT scan, but to the CT scan that was done at baseline of this therapy. We sometimes see patients where radiology report says progression, but progression is a few millimeters on 3 lymph nodes; that’s not real progression, continue with the therapy, patient is doing well.

We sometimes see reports that say, “no progression,” but the patient has been on the same therapy for 9 months, and you actually look at the CT scan from 6 months ago and it’s pretty obvious that there has been a significant growth in the cancer. So, I think that, yes, we need to work closely with our radiologists, but we need to look at the CT scans along with the patient.

Robert J. Amato, DO: I totally agree with that. Radiologists do what they do well. Current scan, what was the last scan? But they don’t go back, and he’s correct; what is the baseline scan, and what are the changes that have taken place? Has this tumor progression slowed down from prior to starting? With these individuals more rapidly progressing, started medication, and you put the red light on there, it’s slowing down. It may not be reversed, but it leveled off, which is; and no new disease is developing; how I look at it. It sounds like Walt looks at it very similarly.

Daniel George, MD: Toni, when you think biologically, disease progression, do you think of existing lesions increasing incrementally as different kind of progression than when you see new lesions, or particularly new organ sites involved?

Toni Choueiri, MD: I do, depending, but then a new lesion could double in size, or everything can be stable and you can have one new lesion, which I usually ablate or remove surgically—not myself, my colleagues of course–and keep on the same treatment. So, I wouldn’t give the example that Walter gave, how do you know progression, but I would say it’s almost like surgery. There are templates, there are textbooks written, how do you do surgery; appendectomy, but at the end of the day it’s really, you cannot, it’s the surgeon who does it. It’s really at the core of the medical oncologist and someone dealing with cancer; a urologist here; that can tell you progression or not.

Daniel George, MD: Rich, what about clinical progression? Now, when we see clinical progression, is that different than radiographic progression in your mind, prognostically and in terms of management?

Richard W. Joseph, MD: Yes. I was going to say that was the one thing that scans for me, at least tell a part of the story, but the most important part for me is the clinical progression. If a patient goes up by several millimeters but his performance status is greatly decreased or something else is going on that is leading me to believe; that to me is more important and those usually go along with other signs that you can see in the bloodwork, perineoplastic, worsening anemia, LDH, calcium. Sometimes those are out of proportion to what the scan shows, so it’s a 3-pronged picture. It’s the clinical status, the scans, and the labs. I agree that there are different types of progression. The ones that have new lesions or typically go along worse than having the growth of old lesions. But I agree, it’s not some textbook. It’s a bit of an art, and there is not an infinite amount of treatments that we have, so I try to milk everything I can out of each treatment before trying to switch to the next one.

Transcript Edited for Clarity