Prostatic disorders in the dog

Common canine prostatic disorders include benign prostatic hypertrophy (BPH ), prostatitis, prostatic cysts and prostatic adenocarcinoma. BPH is a spon taneous and age-related disorder of intact male dogs, which occurs in more than 80% male dogs over 5 years of age, and which is associated with clinic al signs of sanguinous prostatic fluid, constipation and dysuria. BPH signs respond to castration or to finasteride treatment (0.1-0.5 mg/kg per os on ce daily), as finasteride inhibits conversion of testosterone to dihydrotes tosterone, causing prostatic involution via apoptosis. BPH often occurs con currently with prostatic infection, abscessation, cysts and neoplasia in th e intact dog, and finasteride-induced prostatic involution may be beneficia l in treatment of all of these conditions except neoplasia. Two studies sug gest that risk of prostatic adenocarcinoma is increased in neutered, compar ed to intact male dogs. Although canine prostatic neoplasia, unlike human p rostatic neoplasia, usually does not respond to androgen deprivation, recen t reports of prostatic intraepithelial neoplasia (PIN) in a high percentage of older male dogs, with and without prostatic adenocarcinoma, suggests th at PIN may be a precursor to adenocarcinoma in the dog as it is believed to be in man. (C) 2000 Elsevier Science B.V. All rights reserved.