When to Initiate Treatment for Patients With Desmoid Tumors
Desmoid Tumor Expert Roundtable - Part 2
Desmoid Tumor Expert Roundtable - Part 2
In this expert panel series, moderator Mrinal Gounder, MD, Memorial Sloan Kettering Cancer Center, New York, New York, leads participants Rashmi Chugh, MD, University of Michigan Medicine, Detroit, Michigan, and Ravin Ratan, MD, MD Anderson Cancer Center, Houston, Texas, in a discussion on desmoid tumors.
In the second video, our experts describe the circumstances for active surveillance and local therapy, such as surgery, cryoablation, and transarterial chemoembolization (TACE).
For Part 3 of this roundtable, please click here.
Transcript:
Mrinal Gounder, MD: Welcome back to Oncology Learning Network. My name is Mrinal Gounder from Memorial Sloan Kettering Cancer Center, and today I'm joined by Dr Rashmi Chugh from University of Michigan, and Dr Ravin Ratan from MD Anderson in Houston, Texas. In this segment of our round table discussion on desmoid tumors, we are exploring when to initiate treatment.
Dr Ratan, for which patients do you recommend active surveillance and when do you initiate treatment, whether it's local or systemic?
Ravin Ratan, MD, MEd: I think this has been a real evolution over the last 10 years and I think it's important to spend some time on, because people who took care of desmoid tumors in their training may not be aware of sort of all we've learned in the recent past.
There've been several prospective experiences in the last few years that have shown that desmoid tumors do not inexorably grow. And in fact, if you watch a patient with a desmoid tumor for long enough, these tumors will often either stabilize or even regress on their own. That understanding, that in a subset of patients these tumors will not continue to grow, has really given us license to try to evaluate how much the tumor is affecting someone's life, and then make a decision as to whether treatment is indicated based on that impact. And I think that's something that's really important to understand.
When I'm meeting someone with a desmoid tumor for the first time, I'm trying to understand whether this is something that is causing them discomfort, causing them harm, or putting them at risk for complications based on the location. Those are the parameters that I consider when I'm trying to decide if someone needs immediate treatment, recognizing that many patients don't. So, for patients where these desmoid are incidentally detected or where they're not sort of causing pain or dysfunction, we will often say this may just be worth watching for a period of time. We will then get serial imaging over a period of several months and get a sense of what the behavior of the tumor is.
There's no firm line that says that this is what you must do to treat a patient. I think it's always a balance of what is the impact of treatment likely to be versus what is the current impact of the tumor, and I think that discussion tends to shift based on the available therapies that we have, as we've sort of entered an era where we may have therapies that for some patients have pretty limited toxicity. I think that's given us license to treat patients that we may not have treated when cytotoxic chemotherapy, for example, was the majority of what we had to offer.
Dr Gounder: Excellent. Rashmi, anything else you want to add? Does this mirror your own practice in terms of whom you recommend active surveillance versus when you would initiate treatment?
Rashmi Chugh, MD: No, I think the points were well made by my colleague here. The challenge is even patients that are having some increasing symptoms, it is always a trade off in terms of what the treatment would entail. And I always tell my patients, we never want the treatment to be worse than the disease. You really have to listen to the patient, carefully consider their symptoms and the trajectory of growth when you think about initiating treatment.
Dr Gounder: Excellent. Dr. Chugh, we'll stay with you. Can you explain to the audience some of the intricacies of localized therapy? Perhaps you can say why is it that surgery is currently not being recommended universally, compared to say 10 years ago. As well as some of the concerns contraindications for radiation therapy, and other local therapies such as cryoablation or trans arterial chemo embolization (TACE)?
Dr Chugh: Excellent question. I think that the gut instinct for most tumors, benign or malignant is “I want it out of me,” right? But I think we've already talked about how even though desmoid tumors do not spread by conventional malignant routes, hematogenously or lymphatically, they do tend to be fairly locally infiltrative. They've often been described, and we could see this in our histologic slides, that these tumors do have these tentacles that extend out from the main epicenter of the tumor, and can often be fairly far-reaching beyond what we can see on MRI imaging or symptomatically. The end result is, when we have removed these tumors surgically, which was as you mentioned common practice earlier, is that oftentimes there was tentacle-like extensions that were far beyond what we could see, and these tumors would recur.
The other problem is that when we remove these tumors, we also remove a lot of normal tissue, normal muscle, nerves, and sometimes we cause more morbidity with the surgery and then end up, with the tumor recurring along with it. And so oftentimes, we don't accomplish anything meaningful by doing surgical resections, and sometimes we cause more harm than good.
We also learned a lot more about how to manage these tumors without using surgery. That's really a huge reason why surgery has fallen out of favor. There's definitely other local therapies that we can use. We talk about surveillance as a very reasonable form of therapy, to try to see if the desmoid tumor will become less symptomatic or recede spontaneously.
We also use radiation treatment. Radiation treatment as we typically think about for malignancies, but can also be very effective for desmoid tumors, although it does take some time for the radiation therapy to kick in. But we don't turn to radiation very often because radiation can have other chronic morbidities, other risks that we often accept when treating malignancies. But for benign tumors, the risk of secondary malignancy, chronic scarring, other organ and muscle dysfunction based on where the radiation is, is usually not acceptable.
Other local therapies that we sometimes employ, as you mentioned, cryoablation is a treatment that's becoming increasingly in favor in certain situations. For those of you who have not used it as much as, it’s inserting freezer probes directly into the tumor, the positive of that is that there is less long, late morbidity, not kind of that risk of secondary malignancy as you've seen with radiation treatment and you're not removing a lot of muscle and other tissues like in surgery. But it also does have its limitations.
Tumors that are over a certain size or in a location too superficial, too close to critical organs can be challenging to perform that type of procedure in. And I also feel like the discomfort during the procedure, and even afterwards is underappreciated.
All of these local strategies have to be considered very individually. And really this is where that whole multidisciplinary expertise comes in, where we have to have providers that are comfortable with desmoid tumors, understand that even if they can do cryoablation on a good portion of the tumor that there's still those tentacle-like extensions that we may not address and it may kind of occur distally after that.
Dr Gounder: Excellent. Thank you, Dr Chugh, and thank you, Dr Ratan for an excellent overview on the role of active surveillance and the timing to initiate at least localized therapies. We will soon talk about systemic therapies.
To the audience, what we've heard so far is that the key takeaway here is that the treatment of desmoid tumors is very nuanced and complex, and therefore it's highly urged that patients be referred to a center of excellence with sarcoma expertise to be seen by a DMT [Disease Multidisciplinary team] group. And while there is a knee-jerk reflex to do surgery, that if you see a tumor, as Dr Chugh mentioned, to have a surgical resection done, in desmoid tumors, particularly this can end up with more morbidities from the treatment such as surgery rather than the disease itself, of course there is a role for surgery in rare situations. If there's a life-threatening situation, of course there's a role for that. But in general, the field itself has moved away from immediate surgery more towards an active surveillance for a brief period of time.
And the people for whom active surveillance may be contraindicated or may not be best are those people for whom they have significant amount of pain, discomfort, or other impairment in their quality of life, sleep and such. And for those people, for whom local therapies being considered, cryoablation or transarterial chemoembolization could be an option. But this should ideally be done at a center of expertise with interventional radiologists who have expertise in treatment of desmoid tumors. Sometimes even these therapies with cryoablation can lead to worse outcomes if it is not done by an interventional radiologist who does not have expertise in tackling these tumors that are in very complex locations, involving nerve as well as vascular structures.
And lastly, in terms of radiation therapy, yes, this is an option, but there's always this risk of radiation associated sarcomas in young people who have their entire life to live with. This has to be done very judiciously and with significant amount of input from a sarcoma DMT program.
With that, I want to thank the audience for watching. Please join us for part three of this round table on the current landscape in systemic treatment for desmoid tumors.
Thank you both for sharing your insights.
