6520 Background: A significant gap exists between Caucasians and African-Americans (AAs) in prostate cancer mortality, possibly due to sociodemographics, disease biology, or treatment. Furthermore, differential access to care at NCI-designated Comprehensive Cancer Centers (NCICCCs) conceivably contributes to this difference. METHODS: Using data from the Los Angeles Cancer Surveillance Program, we studied the underlying causes of differences in mortality in 18,790 men (AAs: 4,211; Caucasians: 14,579) diagnosed with prostate cancer between 1998 and 2003, and followed until 2006. Three NCICCCs serve this area: USC-Norris, UCLA-Jonsson, and City of Hope. RESULTS: Median age at diagnosis was 67.5 yrs; AAs were significantly more likely to have lower SES; carry no insurance; have distant disease; and be managed with "watchful waiting." The overall and prostate-specific survival was significantly superior for patients treated at NCICCCs, and for Caucasians (Table). Multivariate analysis, after adjustment for sociodemographics, race, insurance, tumor-related factors, and treatment-modality, revealed that treatment at NCICCCs was associated with lower overall (HR=0.74, 95% CI=0.6-0.9) and prostate-specific mortality (HR=0.69, 95% CI=0.5-0.97). AAs were less likely to utilize NCICCCs (OR=0.42, 95%CI=0.4-0.5). Finally, adjustment for sociodemographic, tumor/treatment-related factors, and treatment site abrogated the racial difference in overall (HR=1.08, 95%CI=0.99-1.2) and prostate-specific (HR=1.11, 95%CI=0.9-1.3) mortality. CONCLUSIONS: Patients treated at NCICCCs have lower mortality compared with other facilities. AAs are less likely to utilize NCICCCs for prostate cancer. AAs and Caucasians have comparable overall and prostate-specific survival, after adjustment for sociodemographic, tumor/treatment-related factors, and treatment site. Future studies are needed to understand barriers and facilitators to utilization of NCICCCs for management of prostate cancer. [Table: see text] No significant financial relationships to disclose.