Abstract P6-08-36: Uptake of preventive surgeries in a prospective cohort of BRCA1/2 healthy women

Abstract

PURPOSE Previous studies referred to uptake of preventive surgeries (PS) in BRCA1/2 healthy carriers in ages older than recommended (35yrs). Since our population has a higher prevalence of BRCA2 mutations (usually associated with an older age at Breast Cancer diagnosis) we proposed to study ages and type of preventive surgeries uptaken by BRCA1/2 women included in prospective follow up. PATIENTS AND METHODS Review of all healthy (without a previous cancer diagnosis) BRCA1/2 carriers included in our program from January 2000 to June 2019. Follow-up started after genetic testing. Men were excluded from this analysis. RESULTS A total of 5504 cases (4021 index, 1483 relatives) consented for BRCA1/2 testing. We identified 238 healthy BRCA1/2 carriers (BRCA2:158 (66.4%) vs BRCA1 80 (33.6%). Median age at genetic diagnosis was 38.9 yrs (16-78). With a median follow up of 4yrs, bilateral adnexectomy (BA) was the most frequent PS observed (45 BRCA2 and 28 BRCA1 cases) with 15/45 % and 6/28% undergoing BA and bilateral mastectomy (BM) simultaneously. Bilateral mastectomy was uptaken by 14% BRCA2 women and 10% BRCA1 women. Median ages for PS were: BRCA2-AB: 47,4 (28-71), BRCA1-AB: 46.7 (37-59); BRCA2-BM: 36.6 (31-52) and BRCA1-BM:42.5 (30-55). Isolated BM was observed in 7 BRCA2 cases and 2 BRCA1 cases. Most of women submitted to BA, also underwent total hysterectomy (HT): 65% for BRCA2 and 61% BRCA1. Most cases (88% non-adherent) adhere to radiological surveillance, 111/238 with annual breast S MRI and mammography. All pts submitted to BM are prescribed at least one breast MRI to check for remaining breast tissue. CONCLUSION Our data reveal that even if, in general, BRCA1/2 women uptake preventive surgeries at a later age that recommended, we observed a strong adherence to radiological (most with breast MRI) surveillance. BA is the PS most frequently observed but, surprisingly for healthy women, most cases also underwent TH. BRCA2 healthy women uptaken bilateral mastectomy at an earlier age than BRCA1 women. It´s possible that BRCA1 women, when deciding for BM also decided for BA. Citation Format: Priscila Nejo, Catarina Bexiga, S. Fragoso, A Mayer, S Santos, P Louro, A Luis, C Moura, Ana Clara, Fatima Vaz. Uptake of preventive surgeries in a prospective cohort of BRCA1/2 healthy women [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P6-08-36.