Serial prostate-specific antigen measurements in men with clinically benign prostatic hyperplasia during a 12-month placebo-controlled study with terazosin. HYCAT Investigator Group. Hytrin Community Assessment Trial.

Objectives: To prospectively analyze whether the treatment of men with clinically benign prostatic hyperplasia (BPH) with alpha blocking agents affects the serum prostate-specific antigen (PSA) levels, and to determine the magnitude of such effect.

Methods: Serial PSA measurements were performed using the Abbott IMx assay over 1 year in 134 men over the age of 55 years participating in the Hytrin Community Assessment Trial (HYCAT). HYCAT is a 1-year, randomized, placebo-controlled, double-blinded study of the alpha1-adrenergic antagonist terazosin. All men had lower urinary tract symptoms and a clinical diagnosis of BPH with an American Urological Association (AUA) symptom index of 13 points or more, an AUA bother score of 8 points or more, and a peak urinary flow rate of less than 15 mL/s. PSA was measured at baseline and at 8, 26, 39, and 52 (end of study) weeks.

Results: Baseline serum PSA levels weakly correlated with patients' age at study entry, and modestly with residual urine (positive correlation) and peak flow rate (negative correlation), although none of the levels were statistically significant. Changes of serum PSA during the course of the study did not correlate with either one of the symptom severity or bother assessment tools, residual urine, or peak flow rate. Mean PSA increased from a baseline of 2.5+/-0.22 ng/mL (mean+/-SE) by 0.5+/-0.11 ng/mL in the placebo-, and from 2.7+/-0.23 ng/mL by 0.3+/-0.11 ng/mL in the terazosin-treated patients (P = 0.36 by ANOVA). There were no differences in the changes in serum PSA when patients were stratified by decade of life according to the age-specific PSA reference ranges, or by the final dose of terazosin (2, 5, or 10 mg daily).

Conclusions: The treatment of men with lower urinary tract symptoms and clinical BPH with the alpha1-adrenergic antagonist terazosin does not affect serum PSA concentration, and thus does not confound longitudinal monitoring of serum PSA levels in patients at risk for prostate carcinoma.