Dihydrotestosterone does not induce prostate adenocarcinoma in L-W rats.

It has been postulated that dihydrotestosterone (DHT) is the active trophic androgen in initiating pathogenic changes in the prostate gland. Groups of prostate cancer-susceptible male L-W rats (age 3 months) were treated with subcutaneous depots of testosterone or of DHT. After 14 months, prostate adenocarcinomas had developed in 24% of the testosterone-treated rats but not in the DHT-treated rats. In the latter rats, the testes were significantly reduced in weight, there was no evidence of spermatogenesis, and serum testosterone levels were not detectable. It appears that DHT as administered to L-W rats had an antiandrogenic effect.