The enigma of desmoid tumors

Opinion statement

Desmoid tumors (aggressive fibromatosis) are rare neoplastic tumors that may occur sporadically or in association with familial adenomatous polyposis (FAP). The etiology of these tumors is unknown, but hormonal, genetic, and physical factors play a role in their development and growth. A distinction is often made between desmoids in patients with FAP and those in patients without FAP, but clinically these tumors are treated the same; the only difference is the preferential intra-abdominal location of FAP desmoids. The goal of desmoid treatment is local control. Choosing the appropriate method for achieving local control may be complex as the functional and cosmetic outcomes of each method must be considered. In addition, because desmoids spontaneously regress, any claim of successful intervention must be viewed skeptically. Local control is mainly achieved by surgical intervention and may be improved with the addition of radiation therapy (RT). For patients who cannot undergo surgery, the options for local control include RT and systemic therapies such as hormones, nonsteroidal anti-inflammatory drugs (NSAIDs), interferon, and chemotherapy. Patients with symptomatic, progressive disease who can tolerate chemotherapy should be presented with the option of low-dose or standard antisarcoma chemotherapy. Although it is unclear which regimen is better, patients appear to have quicker responses to the standard antisarcoma therapy. Hormone therapy, NSAIDs, and interferon are used often, with varying success, and should be reserved for minimally symptomatic patients or for patients who do not want or are not candidates for chemotherapy. The treatment of desmoid tumors remains an enigma. As more options become available, selecting the correct therapy becomes more nuanced. Further clinical trials are needed to help the clinician navigate his or her way through the morass of desmoid tumor therapies.