A total of 54 women with BRCA1/2-associated breast cancer treated with BCS and whole breast radiotherapy were matched for age, tumor size, and time of surgery with 162 patients with sporadic breast cancer who had the same treatment between February 1994 and October 2007. Primary end points were cumulative incidence of IBTR and contralateral breast cancer (CBC). Median follow-up was 4 years for both groups.