Abstract 2134: Disaggregating breast cancer mortality trends in Asian American women from 2005-2020

Abstract Background: Breast cancer (BC) is the second leading cause of death among women and has disproportionately higher rates of mortality in certain racial groups, including Asian Americans (AA). While differences in BC mortality between AA and other racial groups have been identified, few studies have disaggregated nationwide AA mortality data. Methods: Using National Vital Statistics System mortality data, BC-related deaths were analyzed among AA groups (Asian Indian, Chinese, Filipina, Japanese, Korean, Vietnamese), Native Hawiian and Pacific Islanders (NHPIs), and non-Hispanic Whites (NHWs) from 2005-2020. We calculated cancer proportional mortality ratios (PMRs), age-adjusted mortality rates (AAMRs), standard mortality ratios, and used JoinPoint regression for average annual percentage change (AAPC). Results: Among 13677 AA, 522 NHPI, 501282 NHW descendants, 14. 3% cancer deaths were due to BC. PMRs increased for all racial groups except Filipina. AAMRs significantly decreased in NHWs (AAPC -1. 61; CI -1. 70 to -1. 48) while significantly increasing for aggregate AAs (AAPC 0. 45; CI 0. 08 to 0. 94). Among AAs, Filipinas had the highest AAMR. AAMRs significantly increased for Asian Indians (AAPC 2. 05; CI 1. 20 to 3. 46), Filipinas (AAPC 0. 61; CI 0. 15 to 1. 46), Koreans (AAPC 2. 72; CI 1. 57 to 4. 65) and Vietnamese women (AAPC 3. 63; CI 2. 26 to 6. 20), but significantly decreased for Japanese (AAPC -1. 41; CI -2. 22 to -0. 53). Conclusions: We observed heterogenous and converging BC mortality trends across AA groups. These trends elucidate which populations within the broader AA group have disproportionately higher death rates and therefore should be targeted for BC prevention protocols (e. g. , Asian Indian and Filipina). Identifying such trends can also help elucidate disparities in cancer care and the overall social determinants that affect women with BC. Understanding disaggregated trends can inform more inclusive screening practices and culturally tailored interventions and treatments to reduce BC deaths in vulnerable populations. Citation Format: Mia Marcotte, Yashi Chauhan, Vedha Penmetcha, Caroline Thompson, Candice Thompson, Malathi Srinivasan, Gloria Kim, Xinran Qi, Robert Huang, Adrian Bacong. Disaggregating breast cancer mortality trends in Asian American women from 2005-2020 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 2134.