Abstract 812: Association of obesity with the early onset and diagnosis of triple negative breast cancer in black women

Abstract Breast cancer (BC) continues to be the most common cancer and the second leading cause of cancer-related death in American women. Furthermore, it affects Black women more adversely than their White counterparts, who experience an early disease onset, diagnosed more often with aggressive triple-negative breast cancer (TNBC) molecular subtype, and face greater mortality. The reasons for these disparities; however, are largely unknown. Here, using a retrospective dataset, we examined the association of body mass index (BMI) with BC early onset and diagnosis with specific molecular subtype in race-based distributions. Study cohort included 1085 BC patients, who visited University of South Alabama Health clinics between October, 2017 and March, 2022. Patients were divided into three BMI (normal weight, NW (24. 9), overweight, OW (25-29. 9), and obese, Ob (30. 0), three age (45 years, 45-65 years, 65 years), and four molecular subtypes Luminal A (HR+, HER2-), Luminal B (HR+, HER2+), HER2 enriched (HR-, HER2+), and TNBC (HR-, HER2-) categories. The data show a higher prevalence of BC in Ob women (46%) than OW (27%) and NW (27%) women of all age groups and its incidence was much greater in Ob Black women (61%) than Ob White women (39%). Further, Black women had nearly twice higher diagnosis at an early age than White women. Moreover, Ob Black women had over 7- and 1. 5-folds higher incidence of early onset BC than NW and OW Black women, respectively, whereas, early onset BC did not exhibit a correlative pattern in White women. Luminal A and TNBC subtypes were the most common in women with early onset BC and Black women exhibited more than twice incidence of TNBC (32%) compared to the White women (14%) of all ages. In contrast, incidence of luminal A subtype was less prevalent in Black (57. 4%) than in White (72. 6%) women. Interestingly, both luminal A and TNBC subtypes were also more prevalent in Ob women; however, the risk of being diagnosed with TNBC increased dramatically in Ob Black women compared to Ob White women. Together, these findings establish obesity as a major underlying cause of early onset BC and TNBC diagnosis in Black women, which could be targeted to diminish the BC disparity gaps. Citation Format: Sarabjeet Kour Sudan, Amod Sharma, Kunwar Somesh Vikramdeo, Wade Davis, Cindy Nelson, Karan Singh, Ajay Pratap Singh, Seema Singh. Association of obesity with the early onset and diagnosis of triple negative breast cancer in black women [abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 812.