Zachary Klaassen: Hi. Welcome to UroToday. We are in Cartagena, Colombia for the SCU 2025 Annual Meeting. Delighted to be joined by Dr. Julian Chavarriaga, who's a urologist here in Colombia, and we're going to be talking today about his keynote lecture on Tumor Markers in Prostate Cancer, a 2025 Update.

Julian, thanks for joining us on UroToday.

Julian Chavarriaga: Hey, thanks, Zach. Thanks for having, no, thanks to UroToday for coming to Colombia.

Zachary Klaassen: It's so great to be here. The hospitality has been fantastic. The meeting's been excellent.

So you give an excellent keynote lecture on tumor markers or biomarkers in prostate cancer, a really state-of-the-art lecture. Let's go back a little bit. We've had PSA for so long, and now we're getting into this personalization of medicine.

Why is it important to have biomarkers to allow this personalization?

Julian Chavarriaga: Yeah, I think that's a great question, and I think if you want to talk about biomarkers, first, you need to understand what a biomarker is.

Zachary Klaassen: Yes.

Julian Chavarriaga: So I think a biomarker is not going to be specifically a molecule. It's going to be like any feature that could prognosticate or predict a response to therapy and guide treatment decisions, helping diagnosis, helping risk stratifying your patients. So that's very important.

And I think, yeah, we had PSA for many years. We had clinical stage. I don't know, we had like MRI recently, but it has really changed and the field has evolved, I don't know, in the last 20 years, maybe, and there's people who's been dedicating their life to doing research in biomarkers.

So I think the final goal of this, I think is to personalize treatment for the patients. The patients may seem similar on the surface, and we may have localized and locally advanced or even metastatic hormone-sensitive prostate cancer patients, and they may seem similar. But they are very different when you look deep down using biomarkers so that I think it's all about personalization.

Zachary Klaassen: Yeah, well said.

The first part of your talk really focused on localized and locally advanced prostate cancer. So maybe just walk us through some of the highlights of that first part of your talk.

Julian Chavarriaga: Yeah. So I think for localized and locally advanced prostate cancer, this is the one that we've been using biomarkers a long time. Maybe we didn't even know we were using them. But we had the clinical stage, we had the PSA, we even had DRE that can predict prognosis as well.

And, well, more recently we had MPMRI. We can use that as a dichotomic and we can, well, like classify as below, or below, yeah, PI-RADS 3 or above PI-RADS 3, and that's going to give prognosis. But I think more recently we have more tools. So our PSMA PET CT is becoming available worldwide. We had it here for a while.

And well, we just saw data recently from the PROMISE nomogram, the version two. The nomogram is very promising, and I know it is going to be used as a prognostic biomarker, at least in this stage of the disease. So that could be used there.

We can use all of these biomarkers like next Monday in the clinic, but we also have, for example, Decipher. Not just to say anything, Decipher has been validated in many, many different scenarios in the localized or locally advanced prostate cancer, either to guide ADT, duration of ADT, whether you give ADT or not in patients with intermediate-risk prostate cancer, biochemical-recurrent prostate cancer, or even to guide active surveillance in some scenarios.

And yeah, more recently I think we've all seen data that is very exciting about artificial intelligence, the ArteraAI, the MMAI, and I think this is very promising in this scenario. We just saw data coming from ASCO showing that Artera can predict the response to abiraterone or ARPIs in patients who have high-risk or very high-risk prostate cancer who are going to receive either intensification or not. And I think this is great because this is going to predict response to treatment.

Zachary Klaassen: Absolutely. And I want to focus on Artera and Decipher because these are really the two robust genomic and digital pathology biomarkers.
How are you using them in your practice currently? I know I use a lot of Decipher for active surveillance. We're starting to use Artera. How are you using it in your practice?

Julian Chavarriaga: Yeah, that's a great question. So Decipher, we have readily available here is that we can use it anytime.

And the thing with Decipher is for our healthcare system, we have... You know we come from a limited resource healthcare, at least in South America. So every Decipher biomarker test is going to increase the cost of treatment for each patient alone. So we don't use it for every patient. We specifically use it in indications that we think has the most strong data. For example, intermediate risk prostate cancer, we decide if we're going to give short-term ADT or not.

High risk, we decide if we're going to go for short-term or long-term ADT, and biochemical recurrence for that as well.

Active surveillance, if we are in a cancer center, tertiary center and we trust our pathologists, we probably don't need Decipher to guide surveillance for that.
And Artera, we don't have it yet. We wish we would, and I think it's going to be a game-changer. But I think it's going to be even easier than Decipher because, well, the only thing you need is the digital pathology slides, clinical information, and that can be sent on a virtual file and just go to fly to the US and we'll get the results back. So we don't have it yet, but hoping to have it soon, yeah.

Zachary Klaassen: I agree. I think the whole artificial intelligence angle of biomarkers is going to be, as you said, it's easy to centralize when it's just a digital pathology slide.

Moving on to your metastatic hormone-sensitive prostate cancer side of your talk, maybe just give us some highlights of what you talked about for biomarkers there.

Julian Chavarriaga: Yeah. So metastatic hormone-sensitive prostate cancer is one area that excites me a lot because I think there's been a lot of movement around that area. And as I say, we were used to say, okay, metastatic hormone-sensitive prostate cancer, you will go for ADT and ARPI. That's what you get. Everyone will get that.

Then we start tuning up and we say, okay, now we're going to decide by volume so you have low volume, high volume. And then we're going to say, okay, let's go a step further, and we say, we're going to certify whether you have synchronous or metachronous metastatic hormone-sensitive prostate cancer. But that's where we stopped.

So I think right now we have way more tools than we used to have. And, yeah, just to say again, ASCO, when we saw data from Emily Grist when you had PTEN inactivations, that is going to predict the response to docetaxel. So I think that is a great biomarker to predict response to docetaxel and whether you're going to give intensifications with chemotherapy to some patients or not.

You can also use Artera. This hasn't been fully approved yet, but we saw data as well. They were using MMAI. Now it's not a big cohort, it's like 300-over patients and they use Artera. Regardless of whether they have low volume, high volume, or synchronous, or metachronous metastatic hormone-sensitive prostate cancer, Artera predicts overall survival very well. So I think this could be used as a pronounced biomarker for now and probably as a predictive biomarker in the future when we have the data. Yeah.

Zachary Klaassen: That's great. No, awesome oversight. I think we're really seeing personalization all the way from active surveillance, all the way to MCRPC. And we just keep getting more data at all these big meetings. It's super exciting.

Just before we wrap up, maybe just give our listeners, educate our international listeners, the state of biomarkers in Colombia or South America. We talked a little bit about Decipher, Artera. How about PSMA-PET? Some of these more sophisticated biomarkers as well?

Julian Chavarriaga: Yeah, that's a great point. So I think, yeah, we have a lot of biomarkers that we can use next Monday in our clinic. We can use PSMA-PET. We have multiparametric MRI of the prostate, PSA. We even have 4K. We have proPSA. We can use all these biomarkers. We have them available.
We don't have them everywhere, so maybe I'm biased because I'm in this cancer center, Bogota is the capital of the city, and we have all these biomarkers available. They're not spread throughout the country, but we do have most of them, and we can use them.

I think one of the main limitations to using some of the most novel molecular biomarkers is cost. That's what's driving the limitation. But all the other ones, we have it.

For our PSMA-PET, for example. I think we do way more PSMA-PET than we should be doing. Yeah. We have it available at a lot of centers, and I think we can use that as a biomarker. We have to train our nuclear medicine physicians to start doing PROMISE and to give us some tools so we can adapt those tools to our clinical practice and just use them for our patients. Yeah.

Zachary Klaassen: Awesome. Anything we haven't touched on? Any concluding statements before we wrap up?

Julian Chavarriaga: No, I think that was a pretty good discussion. Again, thanks for having me, and it's a pleasure to have you guys here.

Zachary Klaassen: Oh, it's such a great pleasure to be here. The country's been welcoming, the SCU has been welcoming. We're delighted to be here for UroToday. Thanks for being here, Julian.

Julian Chavarriaga: Thanks.