AbstractBackgroundAmericans Indians and Alaska Natives face disparities in cancer care with lower rates of screening, limited treatment access, and worse survival. Prostate cancer treatment access and patterns of care remain unknown.MethodsWe used Surveillance, Epidemiology, and End Results data to compare incidence, primary treatment, and cancer-specific mortality across American Indian and Alaska Native, Asian and Pacific Islander, Black, and White patients. Baseline characteristics included prostate-specific antigen (PSA), Gleason score (GS), tumor stage, 9-level Cancer of the Prostate Risk Assessment risk score, county characteristics, and health-care provider density. Primary outcomes were first definitive treatment and prostate cancer-specific mortality (PCSM).ResultsAmerican Indian and Alaska Native patients were more frequently diagnosed with higher PSA, GS greater than or equal or 8, stage greater than or equal to cT3, high-risk disease overall (Cancer of the Prostate Risk Assessment risk score ≥ 6), and metastases at diagnosis than any other group. Adjusting for age, PSA, GS, and clinical stage, American Indian or Alaska Native patients with localized prostate cancer were more likely to undergo external beam radiation than radical prostatectomy and had the highest rates of no documented treatment. Five-year PCSM was higher among American Indian and Alaska Natives than any other racial group. However, after multivariable adjustment accounting for clinical and pathologic factors, county-level demographics, and provider density, American Indian and Alaska Native patient PCSM hazards were no different than those of White patients.ConclusionsAmerican Indian or Alaska Native patients have more advanced prostate cancer, lower rates of definitive treatment, higher mortality, and reside in areas of less specialty care. Disparities in access appear to account for excess risks of PCSM. Focused health policy interventions are needed to address these disparities.