Expanded role for fine needle aspiration of the prostate. A study of 335 specimens

In 279 patients, 335 cytologic samples were obtained from the prostate and correlated with histology obtained by core needle biopsy in 189 cases. Approximately 6% of the cytologic specimens were inadequate for diagnosis. The unconfirmed positive rate for malignancy was 1.6%, the false-negative rate was 27.9%, and the accuracy rate was 89.6%. Granulomatous inflammation was diagnosed in 19 cases, and three cases of tumors other than acinar carcinoma of the prostate were encountered. Based on our experience, cytologic criteria for the diagnosis of prostatic adenocarcinoma are described.