Disparities in stage at presentation for disaggregated Asian American, Native Hawaiian, and Pacific Islander (AANHPI) groups with breast cancer.

1119 Background: Cancer is the leading cause of death for AANHPI populations, who represent one of the most diverse and fastest-growing racial/ethnic groups in the US. Prior research has shown that AANHPI patients in aggregate have a lower risk of breast cancer than Non-Hispanic White (NHW) peers. However, within-group disparities in stage at presentation remain largely unexplored and are important given disparate access to primary care and cancer screening in certain populations. Methods: Data from 2004 to 2020 were extracted from the National Cancer Database (NCDB) for women newly diagnosed with breast cancer. Patients were disaggregated into AANHPI subgroups based on indigenous history or country of origin. Ordinal logistic regression, adjusting for clinical and sociodemographic factors, was used to calculate adjusted odds ratios (AORs), with higher AORs signifying more advanced stage diagnoses, from Stage 0 to IV. Results: Out of 2,563,180 patients with breast cancer, 83,315 (3.25%) identified as AANHPI. Compared to NHW patients, AANHPI patients were younger (median age, NHW: 63 years vs. AANHPI: 58 years, χ2 P<0.001) and more likely to be uninsured or on Medicaid (NHW: 51% vs. AANHPI: 58%, χ2 P<0.001). The largest AANHPI subgroups were Chinese (n=18,708), Filipino (n=18,429), Indian/Pakistani (n=16,424), Korean (n=6,548), and Vietnamese (n=5,345). Stage 3 or 4 disease was more common among NHW than AANHPI patients (11.3% vs 10.7%, χ2 p<0.001). In aggregate, AANHPI patients were less likely to present with later-stage disease (AOR: 0.88, 95% CI 0.87-0.90, p < 0.001). AANHPI disaggregation revealed that Hawaiian (AOR 1.13, 95% CI 1.07–1.21, p < 0.001), Hmong (AOR 1.86, 95% CI 1.34–2.60, p < 0.001), Laotian (AOR 1.46, 95% CI 1.23–1.74, p < 0.001), and Pacific Islander patients (AOR 1.25, 95% CI 1.16–1.34, p < 0.001) were more likely to present at a more advanced stage relative to NHW patients. Relative to Chinese Americans (the largest AANHPI subgroup), all AANHPI patients were significantly more likely to be diagnosed at a later stage of disease. The largest odds were observed in Hmong (AOR = 2.60, 95% CI 1.87–3.62, p < 0.001), Laotian (AOR = 2.00, 95% CI 1.68–2.39, p < 0.001), Pacific Islander (AOR = 1.71, 95% CI 1.59–1.84, p < 0.001), Hawaiian (AOR = 1.54, 95% CI 1.44–1.65, p < 0.001), and Kampuchean (AOR = 1.42, 95% CI 1.20–1.68, p < 0.001) patients. Conclusions: This disaggregation study finds disparities in the stage of breast cancer at presentation across AANHPI groups, with patients of Hawaiian, Hmong, Laotian, and Pacific Islander descent more likely to be diagnosed at advanced stages when treatments are more intense and cure less likely. Research which considers AANHPI patients as a monolith masks poor outcomes from disparate subgroups that could benefit from targeted, culturally tailored interventions that involve community leaders and leverage cultural norms.