Desmoid tumors: need for an individualized approach

Desmoid tumor, also known as aggressive fibromatosis or desmoid-type fibromatosis, is a rare monoclonal, fibroblastic proliferation arising in musculoaponeurotic structures. Although histologically benign, desmoids are often locally invasive and associated with a high local recurrence rate after resection. Since it is a heterogeneous disease, in particular regarding clinical presentation, anatomic location and biological behavior, treatment should be individualized to reduce local tumor control failure with concurrently acceptable morbidity and preservation of quality of life. Many issues regarding optimal treatment of desmoids remain controversial. However, wide surgical excision remains the treatment of choice, except when surgery is mutilating and is associated with considerable function loss or major morbidity. Involvement of surgical margins is probably associated with an increased risk of local recurrence. Postoperative radiotherapy results in a significant reduction of the local recurrence rate, but only in the case of involved surgical margins. Radiotherapy for gross disease is considerably effective, but is associated with a relatively high rate of complications, which are usually mild or moderate and radiation dose dependent. Radiotherapy should only be applied where anatomic constraints preclude complete resection and radiotherapy is not too toxic. Risk factors for local tumor control failure include young age, large size, presentation as recurrent disease, limb/girdle or intra-abdominal location, involved surgical margins, omission of radiotherapy, radiation dose less than 50 Gy and insufficient radiation field size. Increased comprehension of the pathogenesis and biological behavior of desmoids resulted in the emerging applicability of systemic therapies and a wait-and-see policy. Systemic treatment may be indicated in patients that have anatomic barriers to effective surgery or radiotherapy. Considering the significant morbidity of surgery and/or radiotherapy for certain locations, especially mutilation and loss of function, and the tumor's natural history, which is often characterized by prolonged periods of stability or even regression, a period of watchful waiting may compose the most appropriate management in selected asymptomatic patients. Attempts to complete eradication of the disease may be worse than the disease itself.