Examination of prostatic secretions for neoplastic cells is made in an attempt to arrive at an earlier diagnosis of carcinoma of the prostate. Secretions are secured by massaging the prostate in the usual manner. Six smears are prepd. and stained by the technic of Papanicolaou. Neoplastic cells differ from normal epithelial cells in that they are larger, have indistinct borders, possess relatively less cytoplasm, and reveal irregular, enlarged and sometimes hyperchromatic nuclei. In a series of 520 consecutive prostatic smears from approx. 480 patients, there were 66 cases of carcinoma of the prostate. Neoplastic cells were found in secretions from 54 of the patients, or 81.8% of the total. If one is careful the chances of "over diagnosis" (false-positive diagnosis) are minimized. Failure to find cancer cells does not necessarily mean that the patient is free of carcinoma. A positive cytologic diagnosis has its greatest merit in cases that are clinically uncertain.