Epidemiology
Also called aggressive fibromatosis; it can appear in the limbs, pelvis, or chest wall. It does not metastasize, but it can infiltrate muscle or fascia; for that reason active observation is often favored before operating.
Basic features
It does not metastasize, but it can invade locally and cause pain or limited function. Desmoid tumors can be associated with familial adenomatous polyposis (FAP) and with changes in the APC gene; for that reason, an evaluation (genetic testing or a colonoscopy) to rule out an underlying polyposis must be considered, especially when there are multiple tumors, intra-abdominal involvement, or a family history. Discuss your personal and family history with your treating team.
Usual treatment
Treatment often starts with active monitoring. When treatment is needed, there are now targeted options (such as nirogacestat, a gamma-secretase inhibitor that blocks the Notch pathway, or sorafenib), as well as hormonal or anti-inflammatory drugs, radiotherapy, chemotherapy, or surgery, depending on the growth, the symptoms, and the location.
Outcomes and prognosis
It does not metastasize. Its course varies: with active monitoring, some stabilize or even shrink on their own, while after surgery local recurrence is not negligible; the plan must be individualized.