The assess the clinical value of different types of surgical procedures and further analyze the effect of adjuvant radiation therapy (RT) for adenoid cystic carcinoma (ACC) of the breast.

Patients with ACC of the breast were identified using a population-based national registration database (Surveillance, Epidemiology, and End Results, SEER). The Kaplan-Meier method and Cox regression models were performed to determine the impact of the surgical procedures and adjuvant RT associated with cause-specific survival (CSS) and overall survival (OS).

A total of 478 patients with ACC of the breast were identified. The median follow-up was 59 months. The 10-year CSS and OS were 87.5% and 75.3%, respectively. For the Kaplan-Meier analysis, the 5-year CSS were 96.1%, 91.8%, 90.2%, and 94.1% in patients that received lumpectomy + adjuvant RT, lumpectomy alone, mastectomy alone, and mastectomy + adjuvant RT, respectively (p = 0.026). In the multivariate Cox analyses, lumpectomy + adjuvant RT was an independent prognostic factor for CSS and OS. Patients that received lumpectomy + adjuvant RT had better survival rates than patients that underwent lumpectomy only (CSS, p = 0.018; OS, p = 0.031) and mastectomy only (CSS, p = 0.010; OS, p = 0.004).

ACC of the breast has an excellent prognosis. Breast-conserving surgery is a reasonable alternative for patients with ACC of the breast, and adjuvant RT after lumpectomy improved survival rates.