PLACEBO-CONTROLLED DOUBLE-BLIND-STUDY TO TEST THE EFFICACY OF THE AROMATASE INHIBITOR ATAMESTANE IN PATIENTS WITH BENIGN PROSTATIC HYPERPLASIA NOT REQUIRING OPERATION

Purpose: We tested the theoretical concept that a selective decrease i n estrogens has a beneficial therapeutic effect on established benign prostatic hyperplasia. Materials and Methods: In a double-blind study 160 patients from 14 centers were randomized between 2 groups to recei ve either placebo or the aromatase inhibitor atamestane (1-methylandro sin-1,4 diene-3 17-dione, 400 mg, daily for 48 weeks). Results: The ar omatase inhibitor decreased the mean estradiol level by approximately 40% and estrone by 60%. The testosterone concentration increased by mo re than 40% and dihydrotestosterone increased to 30%. Analysis of clin ical parameters showed no difference between placebo and atamestane. C onclusions: The counter regulatory increase in androgens may counterba lance any positive effect of the decrease in estrogens to preserve int raprostatic homeostasis.