University of California researchers have demonstrated that annual prostate-specific antigen (PSA) screening may have a greater impact on reducing prostate cancer-specific mortality (PCSM) in Black men than in White men.
At present, the U.S. Preventive Services Task Force recommends that, for men aged 55 to 69 years, “the decision to undergo periodic PSA-based screening for prostate cancer should be an individual one and should include discussion of the potential benefits and harms of screening with their clinician.”
They acknowledge that African–American men in the US are more likely to develop and die from prostate cancer than White men but were unable to make a separate recommendation for this group due to underrepresentation in clinical trials and thus a lack of data on the specific benefits versus harms.
The American Cancer Society also “recommends that men have a chance to make an informed decision with their health care provider about whether to be screened for prostate cancer.” They additionally suggest that if no prostate cancer is detected on the initial screening, future tests should take place every year among men who have a PSA level of 2.5 ng/mL or higher and every 2 years for those with a lower PSA level.
To address the race-related information gap, Brent Rose and colleagues from the Department of Radiation Medicine and Applied Sciences at the University of California in San Diego reviewed data for 45,834 veterans aged 55 to 69 years (mean, 62.7 years) who were diagnosed with intermediate-, high-, or very high-risk prostate cancer between 2004 and 2017. Of these, 31% were non-Hispanic Black and 69% were non-Hispanic White.
They report in JAMA Oncology that at diagnosis Black men were, on average, significantly younger than White men (61.8 vs 63.1 years) and had significantly higher mean PSA levels (15.1 vs 13.0 ng/mL).
Overall, 61.4% of Black men and 61.5% of White men had at least one PSA screening test in the 5 years before prostate cancer diagnosis, with a respective 9.7% and 9.9% undergoing annual screening.
During a median 77 months of follow-up, 5.4% of participants died of prostate cancer overall and the researchers found that the PSA screening rate was associated with a statistically significant 44% reduction in the risk for death among Black men and a significant 42% lower risk in White men. Of note, there was no significant difference between the two groups in the rates of regional or metastatic disease at diagnosis.
Although the benefits of screening were similar between the two groups overall, when Rose and team analyzed the data by screening frequency, they observed larger differences in PCSM between annual screening and any screening among Black men than among White men.
Specifically, after 10 years of follow-up, Black men receiving annual screening had a cumulative PCSM rate of 4.7%, whereas those who received between one and four PSA tests during that time had a cumulative PCSM rate of 7.3%.
For White men, the corresponding incidence rates were 5.9% and 6.9%.
After adjusting the data for potential confounders, the researchers showed that annual screening was associated with a statistically significant 35% lower risk for PCSM relative to some screening in Black men, whereas the risk reduction was a nonsignificant 9% among White men.
They say this suggests “that annual screening may be particularly important for Black men.”
The authors continue: “These results may be biologically plausible because a shorter screening interval may be valuable for detecting aggressive disease, which is more common in Black men.”
However, Rose and team conclude that “[f]urther research is needed to identify appropriate populations and protocols to maximize the benefits of PSA screening.”
