Background: Desmoid tumors are rare and exhibit a highly unpredictable natural history. We sought to analyze prognostic factors associated with recurrence in a large single-institution study of patients with desmoid tumors.
Methods: We performed a retrospective review of 177 patients with desmoid tumor who underwent macroscopically complete surgical resection, with or without the addition of radiotherapy (RT) or systemic therapy, from 1970 to 2009. We examined patterns of presentation, all known risk factors for recurrence, and their association with recurrence-free survival (RFS).
Results: Twenty-two patients (12 %) had intra-abdominal desmoid tumors, and 155 (88 %) had extra-abdominal tumors. Patterns of presentation included primary (n = 133, 75 %) and locally recurrent (n = 44, 25 %) disease. Treatment was surgery alone in 125 patients (71 %), surgery and RT in 36 (20 %), and surgery and systemic therapy with or without RT in 20 (11 %). Median follow-up was 40 months. Overall, the local relapse rate was 29 %, and 10-year RFS was 60 %. R0 resection status was the only predictor of freedom from local recurrence on multivariate analysis (odds ratio 0.32; 95 % confidence interval 0.15-0.66; P = 0.002). The selective use of adjuvant RT appeared to improve local control in patients with positive margins.
Conclusions: For patients with desmoid tumors undergoing surgery, wide excision with negative margins should be the goal, but not at the expense of function, as fewer than half of patients with positive margins will experience recurrence.