Abstract PS3-01-22: Targeting Disparities: Impact of Mammographic Screening and Social Drivers on Advanced-Stage Triple-Negative Breast Cancer in Vulnerable Populations Across US Counties

Abstract Background: Triple-negative breast cancer (TNBC) is an aggressive subtype with disproportionate mortality among underserved populations. Mammographic screening reduces breast cancer mortality, but disparities in access and utilization persist, particularly in African American (AA) communities and socioeconomically vulnerable areas. This study aims to quantify the relationship between mammography uptake, demographic factors, and social determinants of health (SDOH) with advanced-stage TNBC (AS-TNBC) across diverse U.S. populations. Methods: We conducted a cross-sectional analysis of 593 counties across multiple states using data from the CDC PLACES database (2020 release, representing 2018 data), the American Community Survey (ACS 2014-2018), and county-level SDOH indicators. Communities were aggregated using the Max-P Regions method to balance TNBC case counts and socioeconomic indices (adjusted for area deprivation index, ADI). Descriptive statistics were used to summarize key characteristics across regions. Then, multivariable Poisson and negative binomial regression models were used to evaluate associations between AS-TNBC diagnoses mammographic screening uptake, demographic (% AA, % Hispanic, % aged