Adjuvant Radiation Therapy Is Associated With Improved Survival for Adenoid Cystic Carcinoma of the Breast

Background: The role of adjuvant radiation therapy (RT) for adenoid cystic carcinoma (ACC) of the breast remains unclear. Materials and Methods: We queried the Surveillance, Epidemiology, and End Results database for patients with breast ACC resected between 1988 and 2005, and divided patients based on the receipt of RT. Univariate and multivariate survival comparisons were made for overall and disease-specific survival. Results: Three hundred seventy six patients met criteria for inclusion. Demographics and staging were similar between groups. Univariate analysis revealed an absolute overall and cause-specific survival benefit of 21% and 7% at 10 years (P = 0.005 and P = 0.12 respectively). In the multivariate analysis, RT was a significant predictor of overall and cause-specific survival with hazard ratios of 0.44 (95% Confidence interval (CI) = 0.22-0.88) and 0.1 (95% CI: 0.01-0.88), respectively. Conclusions: RT after local surgical therapy for ACC of the breast improved both cause-specific and overall survival. Use of RT in this rare tumor should be considered in patients otherwise eligible for RT. J. Surg. Oncol. 2010; 102: 342-347. (C) 2010 Wiley-Liss, Inc.