Wilms Tumor Rapid Fire: Update Course 2015

Symposium for the rapid fire session, a child presents who's 5 years old with what I call giant bilateral kidney tumors, almost kissing in the midline, uh, and on CT scan, there's positive lymph nodes that are large as well as a lung metastasis. Uh, this is what the tumor looks like on the MRI scan. This is the left sided tumor, as you can see, it's a, it's a very large tumor encompassing. Uh, 3 quarters of the abdomen and then on the right side you've got 2 tumor lesions on the right kidney. So my question to the, to the group is, uh, what's your next step? Do you biopsy this? Do you try and resect it, or do you just start chemotherapy? That's that's my chemotherapy. Any other opinions? So no one here would biopsy it. So, correct, uh, the, the current status is just to start chemotherapy. Probably 2 cycles get shrinkage, and when you stop seeing any shrinkage, and when we speak about shrinkage, you're talking about a decrease in 50% of tumor size. Well, this child stopped shrinking, and at this size, after 2 cycles, there was no further shrinkage. Uh, and you have what, what you can see on residual, the very still large left renal tumor. And on the right side, you can see the, on the right side, you can see the two tumors in this area over here. So, what is our, our next step here? I ask the panel, is there, uh, what would you do here? Would you, would you go in and resect both tumors? Would you remove the left kidney and try do nephron sparing surgery on the right kidney? Um, or would you continue with chemotherapy? Mm I heard a hm. And that was me. So I want Dan to answer this because he knows this much better. Would you, Dan, would you, would you remove the primary and, and, I mean, the left side and do nephron sparing on the right? Or would you, is that what approach would you take? So the concept, obviously with chemo, right? So the concept is obviously to make sure that you preserve as much kidney tissue as possible and without just seeing that one cut, don't know whether you could do nephron sparing surgery. It certainly doesn't look like you could do it on the central one, although you might be able to. The other issue is whether if you change to a more aggressive chemotherapy regimen, if there are, uh, because it has not been biopsied, if there are anaplastic elements in there that would respond with a more aggressive chemotherapy regimen, then you might move more toward being able to preserve kidney tissue. So I think if you can't do nephron sparing tissue, I would biopsy it and make. The problem with biopsy is they're heterogeneous tumors and you might miss foci of of um. Um, anapplasia, so some would argue just, just change the chemotherapy regimen to something more aggressive. What about taking out the left because that's Doesn't look too promising and using that as your biopsy. Um, to take out the lift and leave the just leave the right, so take out the left, find out if there are any elements that would guide your therapy and hope that you can further shrink the right to allow for nephron sparing. Uh, you could do that. I um. Um, I suspect that if it was only 2 cycles of chemotherapy, we'd probably change to a different chemotherapy regimen. It's hard to know that it's stopped responding after 2 rounds though, so it's um. So, so in general, what we, what we do is, uh, if it stops shrinking, and because most of these are favorable histology Wilms tumor, we will then approach a surgical intervention. Um, when they often stop shrinking, it's usually because of mesenchymal differentiation and not so much an anaplastic tumor, but Dan makes a good point that there could be a, could be a heterogeneous tumor with different phenotypes. So what we do is we always try to do bilateral nephron sparing, and most of the time, surprisingly, you can actually do it. And what we do, our, our technique is, is actually to put the kidneys on ice, especially the left side, clamp the vessels, and then the sharp dissection, uh, remove the tumor, and it's quite, quite interesting, and we've got a, quite a big series now because we have, uh, uh, Jeff Dome who's sort of the head of the Worm's tumor Study Group in, in Washington DC, uh, but it's quite surprising how you can save it. So that's what we did. We saved both sides, uh, and did the left upper pole, and this is the pathology that came back that you can see on the screen. Uh, left upper pole was favorable wombs. The left lower pole was anaplastic. The right tumors were both favorable, and the lymph node had anaplastic tumor. So now that you know that there was some anaplastic tumor in the left side, uh, what is your next, your next stage? What do you do? Do you just keep going with changing chemotherapy? The kids, the child is gonna get radiation on both sides. Either way, because this is rarely stage 3 local tumor, although this was a stage 4. So what, what would your, what would anyone, uh, recommend doing, uh, at this point? Let me, let me cut to the chase. I was away. I'd left town because I never like to stick around for post-op complications. I, I'm that's a joke, sorry. Um, I, I, uh, I actually, uh, went away about 4 days later and in the 5th or 6th day, the pathology came back as anaplastic. I was pretty confident that we got the tumor that looked like gross tumor out and, uh, but the, our oncologist felt that because there was anaplastic differentiation, it was necessary to go get the left side. I argued that the lymph node had anaplastic tumor, so it was really outside, and we did the nephron sparring. Nevertheless, one of my partners went back, I did the left kidney, and there was no tumor in the remaining left kidney, neither favorable wilms nor anaplastic tumor. Nothing they identified, right? How do you know for sure there wasn't? Well, they, they do section through the tumor. They gotta look a lot. You have to look a lot. That's very true, because recurrence for an anaplastic recurrence would be a very, would portend a very bad outcome. This is true. Salvage is difficult, especially with an anaplastic tumor, despite the chemotherapy. This is true. So I think in general, although we have one now, uh, who does have some anaplastic elements, but it's in the central part of the tumor that I removed. And so I think it would be appropriate, we'll see, not to go back and take it out. But I think that was a, that was a reasonable thing to do. Any comments on that case, Dan, do you, would you have done things differently? Um, I don't think so. I, again, you have to go with the philosophy that you're doing the best you can to preserve renal tissue when you have bilateral tumors, and that's why we no longer biopsy them upfront. They're treated. If they don't respond, and Bob Shamberger's made the point that if you have a tumor that's not responding, then you do need tissue to make sure it's not got anaplasia in it. I think when you take the tumors out, you preserve both kidneys, which is, you know, a tribute to the technical experience that you all have. But you get anapplasia, then it really becomes a question because, as I said, once you get a recurrence, it's very hard to salvage that job. One of the issues is you don't really know, and this is a debate and an argument from a pathologist's point of view. Was, was the anaplasia there initially or secondary chemotherapy, did it differentiate into an anaplastic phenotype? I think most pathologists think that the anaplasia was there primarily, so you have really a heterogeneous type of tumor. You also have multifocal tumors, which is also another poor, you know, I think. And I can't quote you the data on it. You may have it, but for multifocal tumors, you would worry about the underlying embryology of that kidney and that you're going to be at risk for developing additional tumors. And certainly if there's mutations in WT1, WT2. So I do want to, I do want to say that the two highlights, and this is, this is what the child looks like now, the left kidney is gone and no residual tumor in the right kidney. Another child, just briefly before I sum up, a 12-month-old child who presented from, from the Middle East with these large tumors after chemotherapy that failed to decrease in size. Uh, we resected them both and saved kidney on both sides, and 7 months later you can see there's really good kidney on both sides with some nephrogenic risks that we are continuing to follow but are unchanged. So, so the message from this is for large bilateral tumors. Um, nephron sparing surgery, you don't need chemotherapy upfront because 97% of these cases are Wilms tumor, and there's only a, a very small percentage of cases that are not Wilm's tumor.