Objective
To determine whether Black Veterans are at higher risk for prostate cancer diagnosis on their first prostate biopsy compared to non-Hispanic White (White) Veterans.
Background
Prostate-specific antigen (PSA) testing is widely used to screen for prostate cancer. Although men of African ancestry display an increased incidence of prostate cancer and more aggressive disease, specific PSA thresholds for biopsy referral have yet to be proposed for this population.
Methods
We used the VHA’s electronic medical record data to collect Veterans’ demographic and clinical characteristics including self-identified race/ethnicity, age, date of first prostate biopsy, PSA results, and prostate cancer diagnosis. Veterans’ ZIP code of residence was used to determine urban/rural status, income, and education. We estimated multivariable logistic regression models to predict the likelihood of prostate cancer diagnosis on the first biopsy using race, baseline PSA, age at first PSA test, age at initial biopsy, smoking status, use of statins, and socioeconomic factors as predictors. We calculated adjusted predicted probabilities of cancer detection on the first prostate biopsy from the logistic models at different PSA levels.
Results
We identified 246,056 White and 71,653 Black Veterans who underwent their first prostate biopsy through February 28, 2020 and who had no previous prostate cancer diagnosis or treatment prior to that biopsy. Black Veterans appeared to receive their first PSA test four years earlier and undergo their first prostate biopsy two years earlier than their White counterparts (median age of 57 vs. 61 and 63 vs. 65, respectively). After controlling for selected covariates, we found that Black Veterans were 52% more likely to be diagnosed with prostate cancer on their first prostate biopsy compared to White Veterans (OR 1.52, 95% CI 1.49-1.55). Our model indicated that a Black Veteran with a PSA of 4.0 ng/ml has an equivalent risk of prostate cancer detection as a White Veteran with a PSA of 9.7 ng/ml.
Implications
Our findings suggested that developing a risk-based PSA threshold for referral to prostate biopsy may lead to earlier diagnosis of clinically significant prostate cancer in a population of Veterans known to have an increased incidence and risk of aggressive disease.