LAUSR

Key Points Question Can patients with breast cancer who carry a BRCA1/2 variant safely undergo breast-conserving therapy (BCT)? Findings In this cohort study, 8396 patients with operable primary breast cancer (187 BRCA1 carriers, 304 BRCA2 carriers, and 7905 noncarriers) underwent BCT, mastectomy with radiotherapy, or mastectomy alone. In multivariable analyses, patients with both the BRCA1 and BRCA2 variants who were treated with BCT had a survival rate at least comparable to those treated with mastectomy with radiotherapy or mastectomy alone. Meaning This study suggests that BCT may be an option for patients who carry a BRCA1/2 variant when the tumor is clinically appropriate for this procedure.