Risk of breast- and ovarian carcinoma after prophylactic mastectomy, and prophylactic salpingo-oophorectomy respectively in carriers of a pathogenic germline variant in BRCA1 and BRCA2

As the data on BRCA1/2-associated breast (BC) and ovarian cancer (OC) prevalence after prophylactic surgery has not been exhaustively investigated yet, we aimed to evaluate the cancer prevalence in a single center cohort of BRCA1 and BRCA2 carriers after conducting prophylactic mastectomy, as well as prophylactic bilateral salpingo-oophorectomy (PBSO) respectively.

We included 875 women with a germline variant in the BRCA1/BRCA2 gene (gPV) diagnosed between 2002-2022 at the Center of Hereditary Breast and Ovarian Cancer of the Technical University Munich Germany. Mean follow up was 7.2 years (range 0-44 years; 95% CI: 6.70 to 7.70). We differentiated BC and/or OC diseased (n=643) and non-diseased BRCA1/2 carriers (n=232).

Our analysis confirmed the effectiveness of prophylactic surgeries in women with a gPV in the BRCA1/2 gene. We observed no BC after prophylactic bilateral mastectomy, 2 contralateral BC after contralateral prophylactic mastectomy and 1 extraovarian serous adenocarcinoma after PBSO. Within the entire study collective, a total of 293 have undergone PBSO, with 6 women having an incidental finding of OC and STIC respectively (=2.0%; 1.7% gBRCA1 and 0.3% gBRCA2).

Our data suggests that mastectomy provides greater oncological safety regarding ipsilateral secondary cancer (ISC) than breast-conserving surgery (BCS). Among patients who had a second BC and were treated with BCS during their first cancer, 18.3% showed an ISC. Within the patients who were first treated with a mastectomy only 4.3% showed an ISC. Further studies will have to be conducted to compare ipsilateral cancer prevalence after BCS and mastectomy.

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Artikel online veröffentlicht:
04. Juni 2025