Dr. Claire de la Calle

So if the lesion is two centimeters and I only have a few millimeters of cancer in my cores, that certainly worries me that the targeting wasn't well done.

And we know that that happens very regularly.

So I think that's very helpful.

In terms of actually using the tumor volume on MRI for active surveillance, we don't really know.

I mean, even studies that just look at PI-RADS score, there's a lot of discrepancy, I think, still in the literature.

And in patients, even patients that have negative MRIs can still progress on surveillance.

So that very much is a question that needs to be answered.

But in practice, if I'm seeing a lesion that I've biopsied

And I find cancer, so now I can call it a tumor to the patient if that tumor is clearly growing on serial MRIs obtained during surveillance.

It's not something I can ignore.

So do I use it?

Yes.

Do we need more research to prove that it's helpful?

Yes.

Yeah.

What about PSA density?

Great question.

PSA density is an important, I think a very important biomarker.

So just going back to just PSA, PSA is actually the only biomarker that's really approved by guidelines for active surveillance monitoring.

And PSA density is an important factor in many, many studies, active surveillance studies.