Racial disparity in the incidence and mortality of young adults with breast cancer: A nationwide study.

• DOI: 10.1200/jco.2025.43.16_suppl.e13804
• Publication Date: 2025-05-28T16:16:02Z
• Authors: Chalothorn Wannaphut; Ben Ponvilawan; Jayalekshmi Jayak...; Sakditad Saowapa; Safa Saadat Afridi; Varsha Gupta; Arya Mariam Roy

e13804 Background: Breast cancer (BC) remains the most diagnosed malignancy among adolescent and young adult (AYA) females, with a steadily increasing incidence over past two decades. Despite significant advancements in care, racial ethnic disparities BC outcomes remain underexplored within this age group. Using data from Surveillance, Epidemiology, End Results (SEER) database, we analyzed impact of race ethnicity on incidence, trends, mortality AYA patients BC. Methods: Female cases 15–39 years between 2000 2021 were identified using SEER Research Plus Data (22 Registries). SEER*Stat (v8.4.4) was used to calculate age-adjusted rates (AAIR), annual percent change (APC), rate ratios (IRR) 95% confidence intervals (CI), R (v4.3.2) for survival analysis. The Cox-proportional hazard model assess factors affecting adjusted treatment, including surgery, chemotherapy, radiation. Results: A total 115,825 identified. Non-Hispanic White (NHW), Black (NHB), Asian/Pacific Islander (NHAPI), American Indian/Alaska Native (NHAIAN), Hispanic accounted 62,081 (53.6%), 17,962 (15.5%), 11,114 (9.6%), 630 (0.5%), 24,038 (20.8%) cases, respectively. Compared NHW NHB females had an increased (IRR: 1.16 (1.14 – 1.18), while NHAIAN, NHAPI, decreased risk (all p < 0.001) (Table 1). AAIR NHAIAN (APC: 1.9%, CI: 0.7–3.2, = 0.002), followed by 1.0%, 0.7–1.3, 0.001), NHAPI 0.8%, 0.5–1.2), 0.7%, 0.5–0.8, NWB 0.4%, 0.1–0.6, higher risks compared (adjusted ratio [HR]: 2.13, 2.03–2.23, 0.0001, HR 1.41, 1.35–1.48, respectively). Conversely, lower (HR: 0.84, 0.78–0.90, 0.0001). Conclusions: Significant exist breast outcomes. In particular, non-Hispanic black have rates, highlighting need urgent personalized interventions address these disparities. Incidence during 2000-2021. Race (NHW as reference) Cancer (female) IRR interval 1.18, p<0.0001) 0.83 (0.77 0.90, 0.91 (0.89 0.93, 0.78 0.79,