Desmoid tumor: Prognostic factors and outcome after surgery, radiation therapy, or combined surgery and radiation therapy

Purpose: To evaluate the therapeutic value of resection and the potential b enefits of and indications for adjuvant and definitive radiation therapy fo r desmoid tumors. Materials and Methods: We performed a retrospective review of 189 consecuti ve cases of desmoid tumor treated with surgical resection, resection and ra diation therapy, or radiation therapy alone. Treatment was surgery alone in 122 cases, surgery and radiation therapy in 46, and radiation therapy alon e in 21. Median follow-up was 9.4 years. Results: Overall, 5- and 10-year actuarial relapse rates were 30% and 33%, respectively Uncorrected survival rates were 96%, 92%, and 87% at 5, 10, an d 15 years, respectively. For the patients treated with surgery, the actuar ial relapse rates were 34% and 38% at 5 and 10 years, respectively. Among 7 8 patients with negative margins, the 10-year recurrence rate was 27%, wher eas 40 margin-positive patients had a 10-year relapse rate of 54% (P = .003 ). Tumors located in an extremity also had a poorer prognosis than did thos e in the trunk. For patients treated with radiation therapy for gross disea se, the 10-year actuarial relapse rate was 24%. For patients treated with c ombined resection and radiation therapy, the 10-year actuarial relapse rate was 25%. The addition of radiation therapy offset the adverse impact of po sitive margins seen in the surgical group. Conclusion:Wide local excision with negative pathologic margins is the trea tment of choice for most desmoid tumors. Function-sparing resection is appr opriate because adjuvant radiation therapy can offset the adverse impact of positive margins. Unresectable disease should be treated with definitive r adiation therapy. J Clin Oncol 17:158-167. (C) 1999 by American Society of Clinical Oncology.