Comparison of spontaneous and experimentally induced canine prostatic hyperplasia

Spontaneous prostatic hyperplasia in the beagle appears to progress with age from a glandular to a cystic histological appearance. Prostatic hyperplasia can be induced in young beagles with intact testes by treatment for 4 mo with either dihydrotestosterone or 5α-androstane-3α,17β-diol, alone, or with either of these steroids in combination with 17β-estradiol. In contrast, the induction of prostatic hyperplasia in young castrated beagles, in which the gland had been allowed to involute for 1 mo, requires the administration of both 17β-estradiol and either 5α-androstane-3α, 17β-diol or dihydrotestosterone. Testosterone and 17β-estradiol, either singly or in combination, did not produce the hyperplastic condition in intact or castrated beagles. The experimentally induced prostatic hyperplasia is identical in pathology to the glandular hyperplasia that occurs naturally in the aging dog with intact testes. However, cystic hyperplasia was not produced by any of the treatments tested in young animals.