Prostate-specific antigen concentration in young men: New estimates and review of the literature

Study Type - Diagnostic (cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Although non-recommended PSA testing has been reported in men younger than 40 years of age, there are few recognized data on PSA in younger American men, particularly younger African-American men, to provide age- and race-specific references. Using data from an existing large study of young, male members of the US military, aged 28-36 years, the present study provides PSA reference distributions for young Caucasian-American men (median = 0.56, 95th percentile = 1.42, range: <0.01-3.34 ng/mL) and African-American men (median = 0.64, 95th percentile = 1.89, range: 0.12-6.45 ng/mL). Previous estimates from the literature are also summarized. OBJECTIVE To provide race-specific prostate-specific antigen (PSA) reference distributions for young men less than 40 years of age who might have undergone non-recommended PSA testing because of their family history of prostate cancer or inadvertently as part of a standard panel of tests. MATERIALS AND METHODS We used data from a large existing study of young, male Caucasian- and African-American members of the US military with stored serum in the Department of Defense serum repository. As part of this previous study, we selected a random sample of 373 Caucasian- and 366 African-American men aged 28-36 years with an archived serum specimen collected for standard military purposes from 2004 to 2006. We measured serum total PSA concentration in this specimen using the Beckman Coulter Access Hybritech PSA assay. RESULTS The PSA level ranged from <0.01 to 3.34 ng/mL among Caucasian-American men, with a median of 0.56 ng/mL and a 95th percentile of 1.42 ng/mL. The PSA level ranged from 0.12 to 6.45 ng/mL among African-American men, with a median of 0.64 ng/mL and 95th percentile of 1.89 ng/mL. The PSA level was significantly higher in African- than in Caucasian-American men (P= 0.001). CONCLUSION The PSA estimates, together with those summarized from the literature, provide age- and race-specific PSA reference distributions for young men who might have undergone non-recommended PSA testing. Comparisons by race could also begin to inform the timing of divergence of prostate cancer risk by race.