Racial impact (asian vs. white) on the prognosis of patients with de novo mcspc: an analysis on latitude, seer and

27 Background: Little is known about the impact of race (Asian or White) on the long-term survival outcomes of men with de novo mCSPC treated with different methods. Understanding racial disparities in survival is critical for accurate prognostic risk stratification and for informing the design of multiregional clinical trials. Methods: This multiple-cohort study included individual patient-level data of men with de novo mCSPC from the following 3 cohorts: LATITUDE clinical trial data (LATITUDE [n=1199]); Surveillance, Epidemiology, and End Results (SEER [n=5496]); and the National Cancer Database (NCDB [n=10366]). Key efficacy outcomes were overall survival (OS) in LATTITUDE and NCDB as well as OS and cancer-specific survival (CSS) in SEER. Kaplan-Meier analysis with propensity score matching (PSM) was used for survival analysis. Hazard ratios were calculated using a multivariate Cox proportional-hazard model. Results: Across all three cohorts, Asian patients diagnosed with de novo mCSPC had better OS and CSS than White patients. In LATITUDE, median OS was significantly longer in Asian than in White men in the ADT+Abiraterone+Prednisone group (not reached vs. 43.8 months, HR 0.47, 95%CI 0.28–0.77, P=0.003 for Cox analysis) as well as in the ADT+placebo group (57.6 months vs. 32.7 months, HR 0.49, 95%CI 0.32–0.75, P=0.001 for cox analysis). In SEER, among all patients diagnosed with de novo mCSPC, median OS was significantly longer in Asian than in White men (53 months vs. 42 months, HR 0.76, 95%CI 0.68–0.85, P<0.001 for Cox analysis). When analyses were restricted to patients who received chemotherapy, Asian men again had longer OS (67 months vs. 41 months, HR 0.70 95% CI 0.51–0.95, P=0.02 for Cox analysis). Using CSS data in SEER resulted in similar conclusions as OS. In NCDB, Asians also had longer OS than White men (whole cohort: 38 months vs. 26 months, HR 0.73, 95%CI 0.63–0.84, P=0.02 for Cox analysis; ADT subgroup: 41 months vs. 26 months, HR 0.75, 95%CI 0.63–0.89, P<0.001 for Cox analysis; Chemotherapy subgroup: 34 months vs. 27 months, HR 0.80, 95%CI 0.69–0.94, P=0.005 for Cox analysis). Conclusions: Asian men had better OS and CSS than White men with mCSPC across different treatment regimens in all datasets examined and should be considered as an independent prognostic factor. This racial difference should also be considered when designing multiregional clinical trials. Further studies including biological analyses are needed to understand the etiology of the apparent survival advantage for Asian men. [Table: see text]