Testicular Androgens in Prostate Cancer Patients Treated with a Luteinizing Hormone Releasing Hormone Agonist

Abstract

Luteinizing hormone releasing hormone agonists have been shown to reduce the levels of androgens in the peripheral circulation and to reduce prostate volume. The objective of this study was to quantify testicular function in patients with metastatic carcinoma of the prostate treated with a luteinizing hormone releasing hormone agonist, leuprolide, by analysis of spermatic vein blood for testosterone and androstenedione, and by determination of the maximum velocity of the 17 ß-hydroxysteroid oxidoreductase enzyme in testicular tissue in vitro. A chemical analysis of the spermatic vein blood of 19 patients with a median age of 78 years revealed the presence of significantly high levels of testosterone and androstenedione, 20.7 ± 1.9μg.% and 6.7 ± 0.7μg.%, respectively. These androgens could not be detected in patients treated with leuprolide before orchiectomy. Patients treated with leuprolide for several months followed by a period of no treatment before orchiectomy secreted testosterone and androstenedione levels comparable to the control group. The maximum velocity of the 17ß-hydroxysteroid oxidoreductase enzyme in vitro in the testes of the leuprolide treated patients was significantly inhibited. Enzyme activity returned to normal levels when leuprolide treatment was followed by a recovery period of no treatment before orchiectomy.