Risk Assessment: How Aggressive is Your Prostate Cancer?

Phillip Koo, MD [00:00:00] So we’ve talked about how you get diagnosed with prostate cancer, you do appropriate testing, you gather a lot of information, you talked about how pathologists grade the tumors, and what a lot the listeners now are aware of is something called risk stratification. It’s sort of a new approach to how we look at cancers, and I’ll admit, sometimes it’s very confusing. So, Dr. Vapiwala, can you walk us through: what is risk assessment and why is it so important? 
 
Neha Vapiwala, MD [00:00:31] Sure, absolutely. First of all, happy to be here. Thanks everybody for joining. I think one way to think about risk stratification is your team of doctors is trying to take all the information we have about your prostate cancer and determine prognosis, right? So they’re really trying to figure out, are you in a category of prostate cancer diagnosis where you’re expected to have a generally good outcome and a favorable outcome after treatment with surgery or radiation, as we’ll talk about, or somebody where there’s more concern about potential spread of cancer beyond the prostate, in which case there may be a role for systemic treatments like hormone therapy and related drugs, or is this a patient where the concern is quite high that you have, you know, the need for perhaps multimodal, what we call, you know sort of multiple attempts at treating with surgery, with radiation, with hormone therapy, and perhaps even intensified hormone therapy. So, when you think about prognosis, that’s really trying to guide what are the expected outcomes and how do we best treat this patient. So, I believe there’s a slide that may demonstrate, you know there’s the classic, what’s called the D’Amico risk groups, which were defined by Dr. D’Amico many years ago. And really took the combination of clinical stage, so typically done with a digital rectal exam, although over the years, that’s moved towards more inclusion of imaging with MRI findings, then what’s called the Gleason score from your prostate biopsy and your PSA level. And then it roughly put patients into low, intermediate, and high risks, as you see on the right here on the slide. But since then, we’ve really evolved quite a bit and more modern risk grouping is what’s in the NCCN. So that’s the National Comprehensive Cancer Network, and these are guidelines that are put forth by experts in the field and reviewed regularly. And really trying to get more granular here. So not only do we still incorporate stage and PSA, but really some additional factors. And I’ll point out here that there’s a newer way that we look at Gleason scores. We went from thinking about Gleason scores to more Gleason grade group. So many of you may have heard, just groups one through five. And that’s a way of essentially lumping and translating. So, Gleason six is group one. Gleason seven, if you’re three plus four, if that’s the breakdown, then you’re considered grade group two. If you’re four plus three, which is still a Gleason seven, but is considered to be a little bit more aggressive, then you’re in grade group three. And then we have Gleasons eight, nine, and 10 in groups four and five. So again, really trying to separate out some patients that used to be lumped as intermediate risk, but might have more favorable or more unfavorable features. And then the same with the very high category. And so, this is just, again, some rough delineation of how we think of risk groups. And then there’s all these new tools that we can use to further refine this, which I’m happy to discuss. 
 
Phillip Koo, MD [00:03:59] Great, so for all the listeners out there, I think this is really important to digest to a certain level that the physicians that are seeing you are taking all these various data points and trying to understand what category you fit in so that they can make the best decisions. Because I imagine how you present different options for patients is very different depending on what are their goals, or what is their physical state, age, a lot of different factors. So, Jim, maybe I’ll turn it over to you. As a surgeon who operates on these patients, how do you digest and look at the risk stratification scores? 
 
Jim Hu, MD, MPH [00:04:40] Absolutely. So I use the I try to explain to patients that that just to just to again clarify and restate that this refers to the risk of recurrence and that’s biochemical recurrence, in which case for surgery we look at a detectable PSA, and it’s important to also understand, for example, and it’s good that we got into this because on some of these genomic tests it’ll predict the five-year and the 10-year risk of metastasis. And as we talked about earlier, you’re getting additional imaging, now typically PSMA PET-CT scans, to see metastatic disease. And so, it’s important to keep in mind, it’s two different things, right? Recurrence is defined by PSA, and typically that PSA recurrence will precede the development of metastatic disease by a number of years, sometimes even four or five years. And so, I try to make sure that patients understand, for example, if they have high-risk prostate cancer, that is, they have grade group four or five prostate cancer. You’re looking at at least a 40% chance of biochemical recurrence. And that helps them, I think. You always want to be optimistic, but I think you also want to prepare people realistically for the journey. 
 
Phillip Koo, MD [00:05:55] Great. You know, it’s it never [fails to] amaze me how sophisticated and nuanced all these different, you know, pieces are in the goals. And you know I think for patients it can be very overwhelming, but I think it’s good to know that if your physicians are on top of this it really has a lot of value and as a field, we’ve really progressed into making better decisions and being able to predict a little bit of what might happen in the future. So, Dr. Vapiwala, from your perspective, radiation oncology, how do look at all this risk stratification. And what has this meant to your practice over the past few years? 
 
Neha Vapiwala, MD [00:06:29] Yeah, absolutely. I mean, exactly as Dr. Hu said, I think about this in the context of risk of what, right? The patient’s sitting there and we throw these terms out, but what are we actually referring to? And it’s exactly as you said, risk of the cancer coming back in most commonly the form of a PSA rise. And so, whether that’s after surgery or after radiation, if that’s the, again, that first sort of sign of something has come back. You know, how do we best direct the patient towards treatment that will reduce the chances of that recurrence as much as possible. And that’s where, as a radiation oncologist, I’m often thinking about, well, certainly if the stage is more advanced or the grade group is much higher, even though the cancer is contained or appears to be contained with the best imaging that we have, a high grade group or perhaps a genomic classifier test that is concerning for potentially more aggressive disease, may at least help me counsel the patient and say, absolutely, you could have surgery alone or radiotherapy alone, but there is this, you know, biologic information that we’re getting from studying your cancer that suggests there could be more than meets the eye. And so, we’re not trying to, you now, place all of our hope and faith in any one test. So sometimes imaging tests can be very reassuring. But I always remind patients they’re not perfect. The staging is not perfect, so we try to take a conglomerate of everything. And then exactly as you said, Dr. Koo, I think the goals of care are very important. So, what are you most worried about as a patient? What distresses you? And if it’s, again, very focused on treatment-related side effects, then we have to incorporate that, because just because I wanna throw the kitchen sink at, you know, a particular diagnosis doesn’t mean that’s what the patient is seeking. So, incorporating that into the conversation, but making sure they really do understand that these risk groups are with the best available data we have, but there are more unknowns than we would like. And so, we do need to think about, are you someone who wants to hedge their bets, be really more aggressive and more comprehensive, or are you somebody who would like to do as little as possible right now, and hope that you don’t need further treatment, but if you do, you’ll take your chances and that’s an important part of the conversation. 
 
Phillip Koo, MD [00:08:57] You know, I think, yeah, I agree. I think that is really important. And hopefully the people listening think about that. I think across the whole journey of prostate cancer care, thinking about what your goals are, to Dr. Vapiwala’s point, really impacts what roads you might decide to go down. We have lots of great questions coming in, please keep them coming through the chat. There were some questions about germline testing, just to reiterate, germline testing is, you know, the genetics, the genes that you inherit from your parents, and you could do, you know, multiple types of tests to figure out what types of mutations you might have. Jim, there was a question about staging, if you mind just quickly talking about staging. What is staging?
 
Jim Hu, MD, MPH [00:09:36] Absolutely, so staging, the way that I think about it from a surgical perspective is, for example, the staging, that could mean two different things, right? Like we typically use what’s called the TNM staging. So, staging for the tumor, for example, is what we talked about earlier. There’s T1C, which is, you know, the reason that there was a prostate cancer diagnosis is because of an elevated PSA. There’s the digital rectal exam, the prostate exams, which Dr. Vapiwala mentioned earlier, are really falling out of favor being displaced by MRIs. But for example, for a person who has a normal prostate exam, but an elevated PSA, that’s gonna be a T2, a local stage prostate cancer. And then if there’s extra capsular, really by feel, and this is, I think, getting more into MRIs now, but let’s say that there’s evidence of spread of the cancer outside of the capsule, that’s T3A or T3B. And this is all confirmed if you have surgery with the surgical pathology, right? And then there’s the nodal status, which we talked about. For example, if there’s only one lymph node involved in the pelvis, that’s N1. If there’s multiple spread throughout the body, for example, we say the area next to the kidneys is the retroperitoneum. And then finally there’s the M, which stands for metastasis. If there is, for example bone lesions or sometimes we see these lesions in the liver. So that’s the breadth of staging terminology. 
 
Phillip Koo, MD [00:11:05] Thank you very much and you know for all the listeners out there it’s very complex you know myself as a radiologist oftentimes I have to remind myself exactly what all the different pieces are and how they’re classified so you’re not expected to know that there’s no quiz but just be aware all this information really is used to help come up with that treatment plan.