Breast cancer inequities: the intersectional role of social epidemiology and tumor biology.

Breast cancer disparities in outcomes remain a persistent challenge in the USA, with survival influenced by neighborhood context, access to resources, and the applicability of existing scientific evidence across populations. These disparities arise from complex, intersectional factors spanning social, structural, and biologic domains. While social determinants of health (SDOH) are strongly associated with breast cancer incidence and outcomes, the causality of biologic mechanisms underlying these associations remain incompletely understood. This review examines breast cancer disparities at the societal level and highlights emerging research that links social epidemiology with tumor biology, emphasizing the need for continued investigation using advanced genomic and epigenetic approaches to better understand and ultimately reduce inequities in breast cancer outcomes.