Background: Among patients with sporadic breast cancer, it is well known that prognoses are similar following breast-conserving surgery (BCS) versus mastectomy. However, previous data assessing oncologic outcomes between BCS and mastectomy in patients with BRCA mutation are limited and inconsistent. Thus, this study aims to compare the oncologic outcomes including locoregional recurrence (LRR), distant recurrence (DR), and overall survival (OS)among this population.