Benign Prostate Specific Antigen Distribution and Associations With Urological Outcomes in Community Dwelling Black and White Men

Abstract

Purpose To describe the cross-sectional associations of benign prostate-specific antigen (BPSA) with clinical urologic measures, and to examine the risk of future urologic outcomes in two population-based cohorts of black and white men. Materials and Methods Two population-based, cohort studies were established to characterize the natural history and risk factors for progression of prostate disease in white and black male residents of Olmsted County, Minnesota and Genesee County, Michigan, respectively. Results The distribution of BPSA levels was similar in blacks (median (25th, 75th percentiles) =32.9 (17.3, 68.0) pg/mL) and whites (median=32.2 (16.6,68.9) pg/mL), p=0.71, but much lower than previous reports. For Olmsted County men in the upper quartile of BPSA, there was a 15-fold increased risk of prostate cancer (CaP; hazard ratio (HR): 14.6 95% confidence interval (CI): 3.1, 68.6) and a 2-fold higher risk of treatment for benign prostatic hyperplasia (BPH; HR: 2.2, 95% CI: 1.2, 4.2) after adjusting for age. After additional adjustment for baseline PSA, the association between BPSA and CaP risk was attenuated, but remained nearly 9-fold higher for men in the upper BPSA quartile (HR: 8.7, 95% CI: 1.8, 42.4). The 2-fold higher risk of treatment for BPH also remained after adjustment for baseline PSA for men in the upper BPSA quartile (HR: 1.9, 95% CI: 0.9, 4.0). Conclusions These results suggest that elevated BPSA level may help to identify men at risk of treatment for BPH and identify men with prostate cancer.

Longitudinal Changes of Benign Prostate-specific Antigen and [−2]Proprostate-specific Antigen in Seven Years in a Community-based Sample of Men

“…The modest age-adjusted correlations between changes in BPSA and [-2]proPSA levels and changes in symptoms and maximum flow rate are consistent with the correlations among annual changes in urologic measures previously reported in this same cohort 24,25 . Additionally, cross-sectionally, the associations between BPSA level and presence of lower urinary tract symptoms or depressed urinary flow rate were much lower than the associations with an enlarged prostate 10 .…”

“…However, as baseline BPSA level increases with increasing age group, absolute levels of BPSA over time will increase across age groups. We had previously found that baseline levels of BPSA were associated with future BPH treatment and diagnosis of CaP 10 . While changes in BPSA levels over time were slightly higher for men who developed an enlarged prostate or CaP, these differences were not significant.…”

“…Stored blood samples from the 4 th , 6 th , and 8 th biennial rounds (1996, 2000, and 2004) were used to measure BPSA and [-2]proPSA levels 10,11 . Serum samples were obtained prior to any prostatic manipulations, including digital rectal examination and transrectal ultrasound and were frozen at −70°C for latter assays.…”

“…Preliminary studies suggest that [-2]proPSA increases the specificity for detecting prostate cancer over PSA, particularly in the 2–10 ng/ml range 5,8 and has also been associated with cancer aggressiveness 9 . Additionally, we previously showed that men with higher baseline levels of BPSA are at greater risk of receiving BPH treatment and that higher baseline levels of both BPSA and [-2]proPSA are associated with future diagnosis of CaP even beyond serum PSA levels alone 10,11 .…”

Screening for Prostate Cancer—Beyond Total PSA, Utilization of Novel Biomarkers

“…BPSA is closely related to prostate volume and does not appear to have any prognostic capacity in terms of distinguishing potentially indolent from aggressive disease [12]. Although serum BPSA alone is unlikely to differentiate between hyperplasia and cancer, in combination with assays for [−2]proPSA, it may allow additional discrimination [13,14]. Intact PSA comprises an additional free PSA subset that has been identified as a potential predictive serum biomarker [15].…”