Diagnosis of prostate carcinoma on biopsy specimens improved by basal-cell-specific anti-cytokeratin antibody (34 beta E12).

The identification of basal cells by the basal-cell-specific anti-cytokeratin antibody 34 beta E12 has been shown to be useful in the diagnosis of prostate carcinoma. To determine the usefulness of 34 beta E12 in prostate biopsies we examined formalin-fixed needle biopsy specimens. In a 17-month period 796 prostate needle biopsies obtained from 293 patients were evaluated on hematoxylin and eosin stains; all 796 biopsy specimens were immunostained as well. Immunostaining with 34 beta E12 reduced the rate of equivocal cases from 5.1% to 1.0% and additionally offered a means of quality assurance by confirming the diagnoses of 61 prostate carcinomas made on the basis of biopsy specimens.