The Role of PSMA PET in Advanced Prostate Cancer Treatment Decisions

In the first segment of this roundtable discussion on the prostate cancer treatment landscape, Dr. Leonard Appleman moderates a panel discussion with Dr. Priyanka Chablani, Dr. Risa Wong, Dr. Zara Kelly, and Dr. Dhaval Mehta on key takeaways from the latest ESMO conference, focusing on the impact of emerging research on clinical practice. The panel dives into advancements in prostate cancer imaging, particularly the game-changing role of PSMA PET/CT technology. They explore its practical applications, how it compares to traditional imaging methods, and its role in treatment decisions for various stages of prostate cancer, including high-risk and metastatic settings. The conversation also addresses the nuances of interpreting these sensitive scans and the importance of collaboration with radiology teams for accurate diagnoses.

Watch part 2 of this series: Are Bone Scans Obsolete? Evolving Imaging Techniques in Prostate Cancer

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Dr. Appleman:
Thank you for joining us. My name is Doctor Len Appleman, I’m a GU medical oncologist at the University of Pittsburgh. And we have a panel here, Doctor Priyanka Chablani, also from the GU group at the University of Pittsburgh, Doctor Risa Wong from our group here at the University of Pittsburgh, Doctor Zara Kelly also and Doctor Dhaval Mehta from our community practice in the Monroeville area, who sees GU cancers as well.

So I think we have a lot of interesting abstracts to discuss from ESMO this year, a lot of interesting data to digest. And most important, to think about how it will be applied in our clinical practice. Before we talk about the exciting therapeutic advances in the field, we wanted to start off talking about what’s been a real revolution in prostate cancer imaging with the PSMA PET CT technology.

I can remember when fluoride PET and fluciclovine PET scan came out for prostate cancer, they never really caught on because they really didn’t necessarily change our management relative to the information we got from traditional CT and bone scan. And sometimes they could even be a little distracting or confusing. I think since the PSMA PET scans have come out, I’ve been surprised at how much I’ve been using it, how many situations it seems to be really helpful in.

So I wanted to open it up to the group. How has it changed your practice?

Dr. Mehta:
So in a community seeing multiple cancers, I always struggle when I have a patient who comes from, you know, early stage localized. I just saw a patient today, intermediate risk unfavorable, and I ordered a PSMA PET at a high risk prostate cancer as a baseline. Once we go to the metastatic setting, I tend to do at least the ones at the diagnosis before they end up going on chemo or combination. But I’m just struggling and I would be curious to know all the experts here to weigh in and share. How are you using, and how often we are doing PSMA PET along the treatment pattern?

Dr. Kelly:
I do think it’s changed practice and there are certain circumstances that we use them in. I think what really has changed it is, a lot of the trials that led to the approval of these systemic agents used conventional bone, used conventional CT, and now we’re in this new era where we’re picking up with these hypersensitive imaging modalities disease that wouldn’t conventionally have been picked up. So I think we kind of have to interpret those old trials with kind of a grain of salt. And then I also think there’s just a lot of nuanced interpreting of those scans.

We’ve, I’m sure I reached out to our, you know, our radiologists just to say, hey, is this, this is super sensitive and it’s picking up this tiny SUV and what do I do with that information? So I think there is nuance, but I agree, you know, in high risk patients, certainly in the localized disease setting, we are using it. Our urologists are commonly using it to help us as well before patients make it to the medical oncology setting.

And then I agree, I use it, you know, depending on the clinical scenario, oftentimes once it’s usually ordered, like I said by our urology colleagues, then subsequently if it’s not going to change management, there’s a nice response. I’ll oftentimes use even conventional imaging depending on the scenario, but I think it’s very patient dependent.

Dr. Wong:
Yeah, I would echo everything that’s been said. I think for a localized prostate cancer, especially for unfavorable intermediate risk or high risk prostate cancer, it gives you more confidence that you’re doing the right thing. It can sometimes help guide radiation if there’s particular spots that that the radiation oncologist might want to target with curative intent. And I think it has led to a lot more metastasis directed therapy for people who have biochemical recurrence, for example.

That’s a prime example of patients who before maybe would have been put on intermittent androgen deprivation. But with PSMA PET, if they only have a few sites of disease, you might target those with SPRT. And I agree with what Doctor Kelly said about there being some nuance with the interpretation. I did have a patient recently who had high risk localized prostate cancer, had APS, my PET scan that was read by the radiologist as having actually diffuse metastatic disease. But then when you looked at the actual scan, the lesions that were called were very low SUV and I wasn’t convinced.

So he had been given an incurable cancer diagnosis, but when I talked to our nuclear medicine colleagues, they thought really that was an over read and he could actually be treated with curative intent. So I do think it’s very important to have a good interpreting radiology or nuclear medicine department that you can kind of discuss these cases with.