Prognostic factors for desmoid tumor: a surgical series of 233 patients at a single institution.

Desmoid tumors are rare soft tissue tumors with limited data on their management and prognosis. We sought to determine the rates of recurrence after surgery for desmoid tumors and analyze factors predictive of recurrence-free survival (RFS). From February 1976 to October 2011, 233 consecutive patients with desmoid tumors who underwent macroscopically complete resection were included in this study. Clinicopathologic and treatment characteristics were evaluated to determine predictors of recurrence. Patterns of presentation included primary (n = 156, 67.0 %) and locally recurrent (n = 77, 33.0 %) disease initially treated elsewhere. Most patients had a R0 resection (n = 169, 72.5 %). In addition to surgery, 43 (18.5 %) patients received radiotherapy and 10 (4.3 %) patients received systemic therapy. Median follow-up was 54 months; recurrence disease was observed in 62 (26.6 %) patients. The estimated 5- and 10-year RFS was 74.2 % (95 % confidence interval (CI), 68.3-80.1) and 70.7 % (95 % CI, 64.2-77.2), respectively. Factors associated with worse RFS were tumor size larger than 5 cm (hazard ratio (HR) = 3.757; 95 % CI, 1.945-7.259; p < 0.001), extra-abdominal tumor location (abdominal wall referent; HR = 3.373; 95 % CI, 1.425-7.984; p = 0.006), and R1 resection status (HR = 1.901; 95 % CI, 1.140-3.171; p = 0.014). Patients were grouped according to the number of unfavorable prognostic factors; the 10-year RFS rates of patients with zero, one, two, and three prognostic factors were 100, 86.9, 48.5, and 34.4 %, respectively (p < 0.001). Regardless of primary or recurrent disease, surgical resection remains central to the management of patients with desmoid tumors. However, there are clearly different prognostic subgroups that could benefit from different therapeutic strategies, and a wait-and-see policy is a possible option for a subset of patients.