IMPORTANCE

Few studies have investigated whether prophylactic salpingo-oophorectomy (PSO) for patients with previously resected breast cancer who carry pathogenic germline BRCA1 or BRCA2 variants is associated with a reduced risk of cancer-specific death.

OBJECTIVE

To assess the association of PSO and prophylactic mastectomy (PM) with prognosis after quadrantectomy or mastectomy as primary treatment for patients with BRCA1 or BRCA2 breast cancer.

DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study was performed in a single-institution, tertiary referral center. Consecutive patients with invasive breast cancer treated surgically between 1972 and 2019 were recruited and followed up prospectively after they were found to carry the BRCA1 or BRCA2 gene variant. The data analysis was performed between April 2022 and July 2023.

EXPOSURE

Following breast surgery, some patients underwent PSO, PM, or both, whereas others did not.

MAIN OUTCOMES AND MEASURES

The primary study end point was overall survival as measured by the Kaplan-Meier method. Secondary end points were crude cumulative incidence of breast cancer-specific mortality, ipsilateral breast tumor recurrence (IBTR), contralateral breast cancer, ovarian cancer, and ovarian cancer-specific mortality.

RESULTS

Of 480 patients included in the cohort (median age at initial surgery, 40.0 years; IQR, 34.0-46.0 years), PSO was associated with a significantly reduced risk of death (hazard ratio [HR], 0.40; 95% CI, 0.25-0.64; P < .001). This reduction was most evident for patients carrying the BRCA1 variant (HR, 0.35; 95% CI, 0.20-0.63; P = .001), those with triple-negative disease (HR, 0.21; 95% CI, 0.09-0.46; P = .002), and those with invasive ductal carcinoma (HR, 0.51; 95% CI, 0.31-0.84; P = .008). Prophylactic salpingo-oophorectomy was not associated with risk of contralateral breast cancer or IBTR. Initial or delayed PM was associated with a reduced risk of IBTR but not with overall survival or breast cancer-specific mortality.

CONCLUSIONS

The study findings suggest that PSO should be offered to all patients with BRCA1/2 breast cancer who undergo surgery with curative intent to reduce risk of death. In particular, PSO should be offered to patients with the BRCA1 variant at the time of breast surgery.