Goals: Sentinel lymph node biopsy (SLNB) is indicated when a mastectomy is performed by Ductal Carcinoma In Situ (DCIS). When mastectomy is performed after one or more attempts of breast conservative surgery (BCS), the need to perform SLNBis questionable. The goal of this study was to determine the histological upgrade rate and SLNB results in this specific group of patients.Methods: Retrospective study of a ca...