DNA flow cytometric study of the hyperplastic and neoplastic canine prostate.

Flow cytometric DNA measurements were carried out on 45 formalin-fixed, paraffin-embedded canine prostate tissues. The tissues were categorized as normal, hyperplastic, or neoplastic on the basis of light microscopic examination, and DNA ploidy was compared with histologic classification. Ten normal prostate samples showed diploid DNA histograms, but with proliferation greater than that found in the normal human prostate. Thirteen specimens of benign prostate hyperplasia showed diploid or near-diploid DNA histograms. Of 22 prostatic carcinomas, 12 were diploid and 10 were aneuploid, with the majority of the aneuploidy being near-triploid. The frequency of DNA aneuploidy recognized in canine prostatic carcinoma is similar to findings in human prostatic carcinoma if all their grades of malignancy are included.