Differences in prognostic factors and survival among white and Asian men with prostate cancer, California, 1995-2004

BACKGROUND. There are very limited data concerning survival from prostate cancer among Asian subgroups living in the U.S., a large proportion of whom reside in California. There do not appear to be any published data on prostate cancer survival for the more recently immigrated Asian subgroups (Korean, South Asian [SA], and Vietnamese). METHODS. A study of prognostic factors and survival from prostate cancer was conducted in non-Hispanic whites and 6 Asian subgroups (Chinese, Filipino, Japanese, Korean, SA, and Vietnamese), using data from all men in California diagnosed with incident prostate cancer during 1995-2004 and followed through 2004 (n = 116,916). Survival was analyzed using Cox proportional hazards models. RESULTS. Whites and Asians demonstrated significant racial differences in all prognostic factors: age, summary stage, primary treatment, histologic grade, socioeconomic status, and year of diagnosis. Every Asian subgroup had a risk factor profile that put them at a survival disadvantage compared with whites. Over-all, the 10-year risk of death from prostate cancer was 11.9%. However, in unadjusted analyses Japanese men had significantly better survival than whites; Chinese, Filipino, Korean, and Vietnamese men had statistically equal survival; and SA men had significantly lower survival. On multivariate analyses adjusting for all prognostic factors, all subgroups except SA and Vietnamese men had significantly better survival than whites; the latter 2 groups had statistically equal survival. CONCLUSIONS. Traditional prognostic factors for survival from prostate cancer do not explain why most Asian men have better survival compared with whites, but they do explain the poorer survival of SA men compared with whites.