Zachary Klaassen: Hi, my name is Zach Klaassen. I'm a urologic oncologist in Augusta, Georgia. We are live at AUA 2025 in Las Vegas. On UroToday, I'm pleased to be joined with Dr. Dan Wiener, who is a pathologist at the Cartersville Medical Center in Georgia. Dan, thanks so much for joining us on UroToday.

Dan Wiener: Thank you for having me here.

Zachary Klaassen: It's a really important topic we're going to talk about today, really how to optimize prostate tissue. And certainly, we are the procurers of the prostate tissue as urologists. But you're the one that tells us what we need to know. So the first question really is, how is the quality so-- how does the biopsy technique, the quality, really affect your ability to give us a diagnosis?

Dan Wiener: Well, to start off, I actually just want to go through how we actually get these biopsies. So because unfortunately, the laboratory tends to be the big black box for everybody. Specimens go in, reports come out. But what happens in between? So when a prostate biopsy is taken, it's transferred to a formalin container either by placing it on a blue sponge, and then that's put into the formalin container, or the needle itself is swished into the container and the tissue is allowed to free float in there.

The tissue is then taken and transported to the laboratory, where the person who's grossing the specimen in, that's the person who processes it, takes the tissue out, and they document the number of pieces that are in there, and the length of the tissue. And then they take that tissue, put it either between sponges, or in a biopsy bag. That's placed into a cassette. That cassette is placed into a tissue processor. After the tissue is processed, the tissue is then embedded in paraffin, in wax, and then is cut in very, very thin slices, which are placed on the slides. Slides are then stained, and those stained slides are what end up on the pathologist's desk.

Zachary Klaassen: OK, so if it's a bad biopsy, if it's got bad integrity, it's fragmented, how difficult does that make your job?

Dan Wiener: It makes it extremely difficult. And actually, you know what would be a good thing? If I could describe to you what an ideal prostate biopsy specimen would be.

Zachary Klaassen: Yes.

Dan Wiener: So an ideal prostate biopsy specimen to a pathologist would be one that is of good size, so something between 1.5 and 2 centimeters in length.

Zachary Klaassen: Right.

Dan Wiener: Of good diameter as well. You want something-- an 18-gauge needle is about 0.88 millimeters. So something in that range. Nothing threadlike.

Zachary Klaassen: Right.

Dan Wiener: The tissue should be intact, one piece. It should be perfectly straight and it should be flat. And when I say flat, not mashed down, but rather that none of the tissue bows up beyond the plane of the rest of the tissue. Everything is sitting in the exact same plane. That, to us, is the ideal specimen.

The thing is, is that prostate biopsies, they deviate from that ideal to varying degrees. And pathologists sort of accept this, or have accepted this. And what ends up happening is we just sort of do the best we can with the tissue that we get. What I can do is I can talk sort of about the limitations, the things that cause us to not give you the information that you need.

Zachary Klaassen: Yes.

Dan Wiener: So there's really three big things. And I'm going to-- I'll discuss each one of them. The first one is the obvious one, the size of the tissue, the piece. It's been shown time and again, bigger biopsy specimens get you better diagnoses. And it makes sense because you're getting a larger sample of the thing. So it more represents the pathology that's occurring in that patient.

Zachary Klaassen: Right.

Dan Wiener: And because of that, when you get these little small specimens, you can't be sure, did we adequately sample that patient?

Zachary Klaassen: Right.

Dan Wiener: So why does this happen? And I think you've talked to Dr. Wystock already about needle design--

Zachary Klaassen: Yes.

Dan Wiener: About it. I don't know if we need to reiterate, but just I'll just brush--

Zachary Klaassen: From your perspective. Absolutely.

Dan Wiener: From my perspective.

Zachary Klaassen: Yep.

Dan Wiener: So really, when you think about how the needle that's being used, which is the workhorse needle that everybody's been using, and how it's been designed, when the needle encounters-- the needle itself has certain limitations. When it encounters dense tissue, it doesn't stay coaxially aligned with the outer cannula. So what does that mean? It means that the distance between the trough of the needle, and the outer cannula, shrinks. And so you get a thinner specimen.

Zachary Klaassen: Right.

Dan Wiener: On top of that, the needle has no real good way of holding the tissue. So when that outer cannula comes sliding down and cut it off, it can push the tissue. And when it does that, you're actually getting a shorter specimen. On top of that, there's another thing that happens, is that there is nothing to protect that tissue from the shearing forces of that outer cannula. So when it hits the tissue, that will cause the tissue to either bunch up in front of it, or tear behind it. And so you get artifactual changes.

Zachary Klaassen: Right.

Dan Wiener: And so that is the first issue. The second problem, actually, the second and third problem, really focus on an area that we really haven't paid much attention to. But we should. And that is the transfer of the tissue from the needle to that formalin container. So we talked about the way we do it with-- the most commonly, people put on the blue sponge these days. Years past, way long ago, everybody just threw it into the formalin container by itself. Then we started learning to put it on the blue sponges.

The thing about this blue sponge is that it doesn't have any adhesive on it. It's not electrostatically charged. And so the only way the tissue comes off is because that surface is very irregular. So it's coming off by friction. So how you have to get the tissue off?

Zachary Klaassen: You scrape it.

Dan Wiener: You scrape it. You take the needle and you either slide it to the side, swipe it, or you drag it along the long axis. And that is very operator dependent, extraordinarily operator dependent. You're dealing with thin, delicate pieces of tissue. And so what happens is if you have somebody who's not experienced, or who has not been trained well, you can get tissue that's been mashed, you get tissue that gets sheared. And when it gets sheared, it gets fragmented.

Zachary Klaassen: Right.

Dan Wiener: And they say, OK, so what? It's fragmented. You have all the pieces there. They're not lost.

Zachary Klaassen: Right.

Dan Wiener: Well, this is the problem from a pathologist when you're looking at the slides. If I find cancer on there, and you've taken more than one core, I have no way of telling you how many cores are involved.

Zachary Klaassen: Right.

Dan Wiener: I also can't accurately give you a percentage of involvement in there. And should you actually want a measurement of the size of that area, which some people do these days--

Zachary Klaassen: Sure.

Dan Wiener: There's just no way to do that. There's absolutely no way to do that. So all of a sudden, from a simple transferring mechanism, you have lost all this information. And we haven't really paid attention to that. The third one is actually, so most people know about the size of the biopsy. And quite a few people know about fragmentation. They see it. They see fragmentation. Something that's been under the radar that really hasn't been addressed, actually even been considered, is tortuosity.

Zachary Klaassen: Right.

Dan Wiener: And what tortuosity basically means is how far does a tissue deviate from being perfectly straight? And where does this happen? It can happen when the tissue is being smeared on that sponge, because one area may catch, another area doesn't, and the tissue gets all wonky. It's my scientific word for it.

Zachary Klaassen: It's perfect.

Dan Wiener: But more commonly, it actually happens when the tissue is placed free floating in formalin. You'd think that that's an atraumatic transfer, and it is. The problem is formalin causes the tissue to contract. And the tissue contracts longitudinally. So imagine taking a string and pushing it in from both ends. What happens?

Zachary Klaassen: It starts getting tortuous.

Dan Wiener: It starts very, very tortuous and wonky. You end up with these specimens that are tortuous, and in three dimensions. And that's an important part. You say, well, it's tortuous, but at least it's a single piece of tissue. Well, and when you take it to the laboratory, you say, well, maybe they can just straighten it out. Once it's been formalin fixed, tissue becomes less pliable. And it's more likely to fragment should you try to play with it too much, especially things like small prostate biopsies.

Zachary Klaassen: Right.

Dan Wiener: There's just no way to do that. And so you're just left with it. But what's the problem that causes it? What does it cause us angst with? So imagine, you have this piece of tissue. And this center part of it is bowed up. It's now sitting in the paraffin block, it's being cut, and the blade is coming across this way. You're going to get tissue, blank space, tissue.

Zachary Klaassen: Right.

Dan Wiener: And the pathologist is going to see that on the slide. And they're going to know that there's more tissue in there because they know in the gross, there's a single piece of tissue there. So they ask for recuts, and which are more levels. And so what does that do? It digs further into the block. And what does that do? It wastes tissue.

Zachary Klaassen: Yep.

Dan Wiener: And it wastes tissue that you could be using for other things. And this happens more commonly than you think. We just don't talk about it.

Zachary Klaassen: Yeah.

Dan Wiener: And it didn't used to be a problem because way back when, you give an answer, you get diagnosis of cancer, you tell them sort of what the percentage is, and you're done. Now, there's so much more that you need to do. You have to save every little bit of tissue that you can. And if you can stop that tortuosity, you can significantly increase the amount of tissue that you save.

Zachary Klaassen: Yeah, it's a great explanation. I mean, it's absolutely perfect because you laid out exactly what the three issues are, and why it's meaningful to us as the clinicians, and you as a pathologist. So just talk a little bit about SUREcore and coreCARE, which are two ways that we can perhaps ameliorate all of these issues.

Dan Wiener: We really haven't addressed these issues in many years because we haven't had a true need to. Now, we do have a need to. And you're talking about the fact that the needle that we've been using has been-- and the way we transfer the tissue hasn't changed in decades.

Zachary Klaassen: Right.

Dan Wiener: So now, companies are looking to do it. And URO-1 has come out with a system, and I do mean a system, with SUREcore and coreCARE, SUREcore being the needle, and coreCARE being the transfer system. So SUREcore, very briefly, because I know you've talked about this already, one of the main differences with SUREcore is the fact that it has these alternating teeth surrounding the central trough. And what does that do? It actually has several functions.

One, it actually keeps the tissue, or keeps the needle coaxial with the outer cannula, regardless of the density of the tissue that it's going through. It also holds on to the tissue. So when that outer cannula comes in and cuts, it holds the tissue in place so you can get a longer specimen. And the third thing is that it protects the tissue from the shearing forces of the outer cannula. So you don't get those artifactual changes.

Zachary Klaassen: Right.

Dan Wiener: And those are very important. And we've seen this actually prove out, because for instance, we've seen that SUREcore, we've seen that SUREcore, about 17 to 22% more tissue by weight with the same gauge needle. So you're getting more tissue just with this new design.

As for coreCARE, so coreCARE is really interesting. coreCARE is a membrane that's on a cradle. And this membrane is electrostatically charged. It's positively charged. And why would that matter? Well, human tissues, including prostate tissue, are generally negatively charged. And so when the tissue in the needle cradle, the trough, touches the membrane, that electrostatic attraction is strong enough to actually pull the tissue out of the trough.

So you have an atraumatic transfer. There's no need to mash down, there's no need to swipe across, there's no need to drag the specimen.

Zachary Klaassen: Right.

Dan Wiener: So what you're doing here really is you're taking the experience level of the person who's doing that transfer out of the equation, because literally, you can show somebody once or twice how to do it. And it's easy.

Zachary Klaassen: Yeah.

Dan Wiener: So what happens with that? So we take the coreCARE in the cradle, drop it into the formalin. It's then fixed, gets sent to the laboratory. And this is another important thing, and one thing that I really like about how well this is thought out, because they thought not only about how it works on the urology side, but also on the laboratory side, because we really don't want to change their workflow.

Zachary Klaassen: Sure.

Dan Wiener: And this doesn't, because the only thing they have to learn is they have to just nudge the tissue slightly to the side to break that electrostatic bond, and once they nudge it to the side, you can just lift it off, put it into between-- you can put it between two sponges in a cassette, and just process it the way you normally would.

Zachary Klaassen: Right.

Dan Wiener: So what you end up with is a straighter, flatter, and less tortuous specimen just from being able to have this atraumatic transfer.

Zachary Klaassen: That's great. I think your point before about how it's such a-- it's super important to transfer this tissue carefully. I think the majority of us take that for granted as urologists. So I think you laid that out perfectly. The last question I wanted to hit on, and it may be obvious, but I want to just dig into it because of the importance of genomics, how does a better tissue, more tissue, allow future genomic testing to be done on these samples?

Dan Wiener: Well, that is actually fairly straightforward, because really, what you're doing is you have not-- you have more volume of tissue up front because with SUREcore, you're getting more tissue. And then, on the other side, you're not having to cut into the tissue to waste it.

Zachary Klaassen: Yes.

Dan Wiener: Because you have coreCARE. So those two things together add up in a way that allow you to have more tissue in your library to be able to do these types of testing. And not just testing for now. We save tissues in paraffin blocks for 10 years.

Zachary Klaassen: Yeah.

Dan Wiener: So when you save tissue for 10 years in paraffin blocks, if something new came out, we'd still have some of it left over. And that doesn't happen a lot if it's not taken off in that sort of way.

Zachary Klaassen: Yeah, great point. It's been an awesome discussion. I've really enjoyed it. Maybe just a couple take-home messages for our UroToday listeners.

Dan Wiener: Sure. So the first one is just the obvious. It's basically the better specimen that you give your pathologist, the better results you're going to get, and information that you're going to get from them. And something a little more specific is, pay a little more attention to that transfer process. Find a process that will allow for that atraumatic transfer like coreCARE, which will allow you to have that atraumatic transfer. And that atraumatic transfer onto the membrane will give you a better specimen.

That better specimen will then allow us to give you not just better results, but also have enough tissue to give you more information, and the information you need to be able to treat your patients.

Zachary Klaassen: Wonderful. Dan, thanks so much for your time on UroToday.

Dan Wiener: Thank you. I appreciate it.