Race and Prostate Cancer: What Do We Know?

Authors


Address correspondence and reprint requests to: Mack Roach, III, MD, Associate Professor, Department of Radiation Oncology, University of California San Francisco, 505 Parnassus Avenue, L-34, San Francisco, CA 94143-0226, U.S.A.

Abstract

Objectives: Is race an independent prognostic indicator of outcome and overall survival in prostate cancer? African American men have been reported to have the highest incidence and mortality rates for prostate cancer worldwide, but the evidence to explain this is confusing at best.

Materials and Methods: A literature search was conducted, and an effort was made to include all articles published in the last 15 years that evaluated the independent significance of race on survival or disease-free survival from prostate cancer. Special attention was given to the major prospective randomized trials in which the initial workups, evaluations, and treatments were relatively uniform and in which the opportunity for confounding variables were small.

Results: The appearance of a difference in outcome due to race is most likely a result of an epidemiologic phenomenon that arises when evaluating two different populations that have different distributions with regard to severity of disease. African Americans tend to present with higher prostate specific antigen (PSA) levels and higher Gleason scores, and a larger percentage are likely to belong to the groups with the higher risk of failure, creating the impression that failure is due to race.

Conclusions: On examination of the prospective randomized trials in the literature, “race-based” explanations for differences in survival should be viewed with a moderate degree of skepticism. So-called “epigenetic” factors may explain the higher incidence of prostate cancer noted in numerous studies.

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