Even though black men are more likely to be diagnosed with, and to die from, prostate cancer, recommendations about prostate cancer screening are primarily based on studies of white men. A recent study led by investigators at Brigham and Women’s Hospital and Harvard T.H. Chan School of Public Health focused exclusively at results among black men. The study addressed whether an optimized screening strategy with baseline prostate specific antigen (PSA) levels predict prostate cancer in this population. The study findings found that baseline PSA levels in black men measured at midlife strongly predicted the risk of total and aggressive prostate cancer in the future.
The researchers found that a single, baseline PSA level measured during midlife strongly predicted subsequent diagnosis of total and aggressive prostate cancer up to 12 years after a blood draw. These findings suggest that targeted screening based on a midlife PSA for black men might identify those at high risk of aggressive prostate cancer. The screenings could also minimize future screenings for those at low risk.
Compared to white men, black men in the U.S. are 2.5 times more likely to die of prostate cancer. However, screening studies to date have largely been focused solely on white men. Therefore the data from this study addresses a critical gap in understanding the substantial racial disparities. It also suggests a potential strategy to reduce prostate cancer death in black men.
The research team involved took a targeted, risk-stratified approach, leveraging data on men enrolled in the federally funded Southern Community Cohort Study, a collection of 86,000 men and women from the Southeastern U.S., that included more than 22,000 black men.
The data showed that 95 percent of total and 97 percent of aggressive prostate cancer cases had baseline PSA above the average for their age group. Compared to men with PSA at or below the age-specific median, men with levels above the median had significantly increased risk of aggressive prostate cancer across age groups. Men with PSA levels above the 90th percentile had the greatest risk.
The research showed that increased risk was seen with PSA levels that were higher than the average but still well within the “normal” range – and low enough not to trigger follow-up in usual clinical practice.
The findings do not necessarily imply that prostate biopsy or definitive treatment is immediately required in younger men with higher PSA levels at baseline. This conclusion could lead to over-diagnosis. However, the researchers determined that these men should undergo more intensive PSA screening to enable earlier identification of cancer and potential cure while still possible.