The effect of nafarelin acetate, a luteinizing-hormone-releasing hormone agonist, on benign prostatic hyperplasia.

We examined the influence of androgens on benign prostatic hyperplasia, using nafarelin acetate, a potent luteinizing-hormone-releasing hormone agonist, to achieve reversible androgen deprivation in men with benign prostatic hyperplasia. Nine patients with bladder-outlet obstruction due to benign prostatic hyperplasia were treated with subcutaneous nafarelin acetate (400 micrograms per day) in an open trial for six months. In all patients, serum testosterone decreased to castrate levels. Objective observations included uroflowmetry, measurement of residual urine volume, determination of prostatic size by ultrasonography, and prostatic biopsy. In all patients, the prostate regressed to a mean (+/- SEM) of 75.8 +/- 3 percent of the initial size (range, 52 to 86; P less than 0.005); the regression reached a plateau after four months. Morphologic analysis of biopsy specimens showed regression of glandular epithelium. Three of nine patients had clinical improvement with treatment. Six months after the cessation of treatment, plasma testosterone levels had returned to normal and the size of the prostate had increased to 99 +/- 5.5 percent of the initial size. These findings suggest that androgens have an important supportive role in established benign prostatic hyperplasia and that testicular suppression will benefit some patients. However, this form of treatment could be applicable only in carefully selected patients who were not surgical candidates, and it would need to be maintained indefinitely.