Active Surveillance Approach Can Avoid Treatment for Desmoid Tumors

Richard F. Riedel, MD

Professor of Medicine

Duke University School of Medicine

Member, Duke Cancer Institute

Durham, NC

Targeted Oncology: What does the Desmoid Tumor Working Group recommend for patients with potential desmoid tumors?

Richard F. Riedel, MD: The Desmoid Tumor Working Group updated the guidelines…and the first thing that you'll notice is that after you make a diagnosis, you watch [with active surveillance].¹ This is how things have changed. We used to do surgery in the vast majority of patients, [but] we found that there were high recurrence rates, repeat surgeries, and morbidity associated with those surgeries. In the last 15 years, there were increasing anecdotes and case series and case reports about spontaneous regressions. Women would go through menopause and these tumors would get smaller. Patients would identify it during pregnancy, and when they stopped breastfeeding, or they got further away from the pregnancy, the tumor would regress.

There are studies that show that from a local control standpoint, you can give radiation, you can give surgery, you can give surgery in combination with radiation, [or] you can watch, and the 2-year progression-free survival [PFS] rate for all those groups is the same.² So, less is more when it comes to desmoid tumors. The guidelines say that you watch for 1 to 2 years.¹ If I have someone who's actively having progression in their pain, I'm not going to wait 1 or 2 years, but in the vast majority of patients, you can watch safely.

Why is active surveillance recommended?

Because the tumor can get better on its own, and the recurrence rates with surgery approach 75%. So, there's a high rate of this coming back, and it can spontaneously regress on its own, and it's not going to be life-threatening for the patient. We hear from patients all the time, “I want it out. Why not just take it out?” I say, “We can take it out, but you need to understand it's going to probably have [recurrence].”

For small, superficial lesions on the abdominal wall—soft tissue—we have these discussions with our surgeons. We will still consider surgery, but it's for a minority of patients. As long as they understand that this surgery may not fix the problem, as there's a high rate that it's going to come back, they can make that informed decision.

What do you do in case of progression?

It depends in part on the location. Surgery currently is only recommended for abdominal wall desmoids, and typically small abdominal wall desmoids, where the morbidity of surgery is considered to be low; otherwise, surgery is not a recommended approach. For a symptomatic or more rapidly progressive tumor [in other locations, we consider] medical therapy.

Can patients with desmoid tumors be treated with radiation therapy?

For surgery, radiation, surgery plus radiation, and active surveillance, the 2-year PFS across the board is the same for all of those. There are prospective data for radiation therapy. The 2-year PFS rate is 80%, which is good, but you're now exposing a younger individual to the potential long-term effects of radiation therapy, because the disease is not expected to be life-threatening.² For the same reason surgery has taken a bit of a back seat, radiation has taken a back seat as well. Active surveillance is at the forefront for minimally symptomatic patients or poor disease that's in a noncritical location.

I have [used radiation therapy] but that's after they failed medical therapy, and it's up against the brachial plexus and they can't move the right arm. Those are situations where we can be a little bit more aggressive.

How do you counsel patients who are concerned about their diagnosis?

The first thing I tell them is that this is not a cancer. The second thing I tell them is that in the vast majority of patients it is not life-threatening. The third thing I tell them is that the natural history of this disease is one that will wax and wane over time and can get better on its own. Some patients will absorb that, and some patients are still resistant and want it out no matter what.

What do the NCCN guidelines on soft tissue sarcoma advise for desmoid tumors?

The NCCN guidelines comment on the Working Group for desmoids, number 1 being [a recommendation to be treated at] centers with expertise, considering [evaluation for] familial adenomatous polyposis [FAP] for young women, and appropriate colorectal screening and then imaging for young individuals with family history of colorectal cancer.³ There are some highlights from the NCCN, and it all depends on the location of the tumor and how morbid is it expected to be as it grows. If it's a non-critical location, if it grows, and it's not expected to be morbid, then you watch.

If it progresses, you [might] still watch. Location is key. If it's in a critical location where any growth is going to be morbid, then you might want to consider treatment sooner. If it's in a non-critical location, and even if it grows, such as in the arm, it's still not going to be much of an issue, you can watch for a couple of scans.

How frequently should you perform imaging to monitor desmoid tumor progression?

In my practice, I will image every 6 months for 2 years, and I move to once a year after that. If something is moving very quickly, I will image every 3 to 4 months to start, particularly if it's in a critical location, because I don't want it to get too much bigger and be a problem. Some [physicians] say, “I don't need to image it. I can see it.” [The patient] can call them if there's a problem. I see them every 3 months or every 6 months, somewhere within that range. The NCCN guidelines say every 3 to 6 months for 2 to 3 years, and every 6 to 12 months [thereafter]. That is what I what I do, and for most patients, I fall on the 6-month cycle at least to start.

_{DISCLOSURE: Riedel previously reported funding to the institution for clinical trial support from Aadi Bioscience, Adaptimmune, AROG, Ayala, BioAtla, Blueprint, Cogent, Daiichi-Sankyo, Deciphera, GlaxoSmithKline, InhibRx, NanoCarrier, Oncternal, PTC Therapeutics, SARC, SpringWorks, TRACON, and Trillium; consulting fees from Aadi Bioscience, Adaptimmune, Bayer, Blueprint, Boehringer Ingelheim, Daiichi-Sankyo, Deciphera, GSK, NanoCarrier, and SpringWorks; honoraria for lectures from SpringWorks; travel support for advisory board participation for Deciphera.}

REFERENCES:

1. Desmoid Tumor Working Group. The management of desmoid tumours: A joint global consensus-based guideline approach for adult and paediatric patients. Eur J Cancer. 2020;127:96-107. doi:10.1016/j.ejca.2019.11.013

2. Mikhael R, Smith M, Tzanis D, Watson S, Miah AB, Bonvalot S. Desmoid tumors: who, when and how to treat?. Curr Opin Oncol. 2022;34(4):335-341. doi:10.1097/CCO.0000000000000854

3. NCCN. Clinical Practice Guidelines in Oncology. Soft tissue sarcoma, version 5.2024. Accessed April 16, 2025. https://tinyurl.com/4hmkn588