Mucinous metaplasia in dogs prostate and its anatomical distribution

Ten dogs prostates, removed during consecutive post mortem examinations, were investigated for the presence of mucinous metaplasia, defined as tall columnar cells containing mucin which is both alcian blue (A.B.)- and periodic-acid-Schiff (P.A.S.)-positive. Five of the prostates were normal, and five showed benign hyperplasia (BPH). Mucinous metaplasia was found, in four of the hyperplastic prostates, and in one of the normal glands, all of them in dogs older than 7 years. It involved mainly the posterior inferior periurethral region suggesting an association with the prostatic utricle. To our knowledge, mucinous metaplasia has not been previously described in dogs prostate.