[Cancer of the prostate with rectal invasion].

Rectal invasion in prostate cancer is an uncommon clinical finding to which little attention has been focussed in the literature. However, it can represent important clinical (rectorrhagia, tenesmus and obstruction), diagnostic (confused with rectal cancer) and therapeutic problems. We report two cases of prostatic carcinoma with rectal invasion, one at the time of presentation and the other during the course of the disease, that illustrate the problems associated with this form of neoplastic spread.