African American women who carry the BRCA1/2 mutation: Clinical characteristics and prevention strategies.

Abstract

10554 Background: Carriers of pathogenic variants (PV) in BRCA1/2 have an increased risk of breast, ovarian, and other cancers . The clinical characteristics and uptake of risk-reducing interventions in African American(AA) women with BRCA1/2 PVs are less well studied. Methods: After IRB approval, we performed a retrospective chart review on African American women seen at Nancy and James Grosfeld Cancer Genetics Center at Beaumont Health from January 1, 2006, to December 31, 2021, who tested positive for a BRCA 1/2 mutation. We analyzed demographics, cancer characteristics, outcomes, and prevention strategies. Results: Of 238 African American(AA) women who underwent genetic testing, 69 patients (29%) were identified to be a carrier of BRCA1/2 PVs or likely pathogenic variants (LPVs). The median age at testing was 49 years (range: 24-87). Forty-six women (67%) had a cancer diagnosis, with a median age at diagnosis of 52 years. Four women had two, and one had three cancers, for a total of 52 cancers. Breast cancer was the most common type of cancer (40; 77%), with a median age at diagnosis of 48 years (range 24-73) and a majority (26; 65%) being BRCA2 carriers. Most were invasive ductal carcinoma (87.8%), high-grade (80%), ER-positive (52%), PR-negative (68%), HER2-negative (94%) and stage I or II disease (63%). Fifteen (38%) were triple-negative. Most patients (87%) received adjuvant systemic chemotherapy or endocrine therapy, 31% received neoadjuvant chemotherapy, and 39% received adjuvant radiation. The 3- and 5-year survival was 94% and 91%, respectively, with a median follow-up of 103 months. Three patients (all BRCA2 carriers ) developed contralateral breast cancer (median time to recurrence: 201 months); 3 (all BRCA2) developed local recurrence (median time to recurrence: 60 months), and 4(2 BRCA1, 2 BRCA2) developed metastatic recurrence (median time to recurrence: 34 months). Other cancers observed were ovarian (n = 6; 4 BRCA2, 2 BRCA1), uterine (2), lung (2), kidney (1), and glioblastoma (1). Compared to AA carriers without cancer, those with cancer were more likely to undergo risk-reducing mastectomy (RRM; 68% vs. 23%) and risk-reducing salpingo-oophorectomy (RRSO; 72% vs. 55%). In the non-cancer group, significantly fewer patients elected RRM (23%) compared to RRSO (55%). Conclusions: Our study outlines the characteristics of AA women who carry BRCA1/2 PVs, revealing that most had high-grade invasive ductal breast cancer with excellent survival. Patients without a cancer diagnosis were less likely to undergo risk-reducing surgery, highlighting the importance of effective counseling focusing on primary prevention in these high-risk patients. Further research is needed to better characterize cancer risk and address potential barriers to uptake of risk-reducing interventions in this population.