Getting Under the Hood of Racial Disparities in Prostate Cancer

Prostate cancer is the most common non-cutaneous cancer affecting men in the US and the second leading cause of cancer mortality. Prostate cancer is also growing as a source of cancer morbidity and mortality globally, with the greatest relative burden of lethal disease born by men in West and sub-Saharan Africa, and in the Caribbean. Age-standardize mortality rates in the US have fallen 50% in the era of PSA-based early detection, but African American men continue to face a roughly 2.5-fold excess burden of lethal disease compared to Caucasian men. The disparity is worst among younger African American men, for whom advanced disease rates are up to 4-fold higher, and may reflect an earlier onset of disease by approximately 5 years. The fact that a racial disparity exists has long been recognized, but the explanations for it remain poorly understood. Potential roots of the disparity include genetic, environmental, and access to care-related factors—and it is almost certain that all three types of factors are partially responsible. African American men are slightly more likely to be screened at younger ages, and less likely to be screened at older ages, compared to Caucasian men. However, overall rates of screening for younger African American men remain too low. The literature is conflicting as to whether African American men are treated differently after diagnosis; in most analyses, race drops out of most multivariable models once other sociodemographic parameters are included. Likewise, raise drops out of most multivariable prognostic models of outcomes, suggesting that while African American men have more aggressive disease on average, this discrepancy is, for the most part, adequately reflected in risk factors like Gleason score and stage. More intensive use of PSA testing at younger ages for African American men would likely go a long way toward narrowing the mortality gap; future research is needed to understand the interactions between potentially modifiable genomic and environmental factors in order to adequately ameliorate the disparity.

Learning Objectives:

1. Understand the evolving epidemiology of prostate cancer in the the US and globally, and the excess burden of disease borne by men of African ancestry

2. Describe the factors, general and specific, that may underlie and explain the racial disparity.