Recurrence and metastasis of epithelioid sarcoma
Hi, I’m Seth Pollack. I’m a medical oncologist and a scientist here at Northwestern University’s Lurie Cancer Center, and I specialize only in sarcomas, which are cancers of the bones and the soft tissues.
Is surgical resection curative in Epithelioid Sarcoma?
In my opinion, I always consider epithelioid sarcoma a high-risk cancer, even for a patient with a really small tumor. This is always a diagnosis that makes my radar go up. “Uh, oh, this is a patient I got to worry about.” But there are patients for sure who are cured with surgery alone. Some patients we’ll give a combination of surgery and radiation to. Every once in a while, though there’s not good data on this subject, some people will use chemotherapy as part of the treatment as well. But there are certainly patients who are cured with surgery.
What is the rate of recurrence and metastasis? Does type of surgery influence recurrence?
The most important thing with the surgery is that they need to get a margin of tissue around the tumor. What that means is that, imagine the tumor is infiltrating into all of the tissues around it; if you just get the tumor, the extensions of the tumor are going to get missed and left behind, even if you think you got it on first blush. So you need a margin around the tumor, which sometimes it’s no problem for the surgeons, there’s nothing that important right there, they can easily get a margin. But sometimes it can be difficult, especially if there’s important anatomic structures that the tumors right up against.
Now, with sarcomas, we know if you try your best to get a margin, and you get a margin that’s good enough microscopically, you’ve gotten the whole tumor, it looks like, under the microscope, but maybe you don’t get as much tissue around it as you want to, for a lot of sarcomas, we know it’s okay to come in and radiation to the surgery to try and increase the chance of cure, to compensate for that lack of good margin.
As I said before, these are always high-risk tumors. There’s two types of epithelioid sarcoma. There’s the proximal type, and there’s what we call the distal type. And they have different prognoses. The distal type means that it’s the type that happens in the extremities like the arms and the legs. The proximal type is the type that happens in the trunk. And especially with epithelioid sarcoma, it happens a lot in the pelvis. And these two types of epithelioid sarcoma are different in terms of where they present, but they’re also different in terms of their biology. And they even look differently to a pathologist looking at them under the microscope. So differently in fact, that you could theoretically have somebody who has a proximal type epithelioid sarcoma that starts in a location that you think of as being distal just because it looks differently under the microscope.
Now, these two epithelioid sarcomas are different in terms of their prognosis. I usually think of the proximal ones as, even though our goal may be cure, the odds are against the patients, unfortunately. That I think usually with those, on average, it’s going to be more than 60% of patients die of their disease. Whereas the distal patients, I think of those patients as having still very high-risk cancers, but maybe the odds, just on average, are a little bit in favor of the patients. Maybe it’s more flipped. So I usually think of that as being maybe 60% of the patients are going to be cured.
And then if you put everything together with the big data sets, I think of it being a little bit closer to 50/50 with these patients when it comes to epithelioid sarcoma and their prognosis. Of course, with every patient who comes in the door, there’s all kinds of factors that can affect these things: the size of their tumor, whether it’s proximal or distal, do they have known lymph node spread? All of these things can affect the prognosis of an individual patient.
Does amputation increase the risk of metastasis?
No, amputation does not increase the risk of metastasis. This hasn’t been done for epithelioid sarcoma specifically, but we know, in soft tissue sarcomas, that albeit not based on the biggest data sets, but in general, amputation doesn’t improve the chance of cure. So long as the surgery is done really well and radiation is given if needed, amputation doesn’t increase the chance of cure. But we don’t think that amputation makes things worse.
Now, what I think sometimes confuses people is that you could have a patient where their tumor is just so nasty, so big that there’s just not going to be any way to do a limb salvage operation. Right? You’re not going to be able to spare that patient from amputation.
Now, that patient with that terrible, terrible tumor where amputation is the only option is going to be at higher risk than a patient who also has epithelioid sarcoma, maybe in a similar location, but the surgeons feel that a limb-sparing operation is possible. And I think that’s where some of these ideas come from, that I don’t think are correct, about amputation increasing the chance of metastasis. I think it’s just because the patients getting an amputation are patients with higher-risk disease.
Are any tumor locations associated with better prognosis?
As I was saying before, the distal ones, the ones in the extremity, they’re definitely better behaved. I think they have a different biology. That is, I think they’re just naturally a little bit less aggressive tumors. But I think there’s also some of these pelvic tumors, it could sometimes be a little bit harder to be as aggressive surgically and with radiation as you’d like to be, just because the location is a little bit hard to get to. So I think both play a factor, but I think probably it’s mainly the biology.