Nuclear volume estimates in prostatic atypical adenomatous hyperplasia

OBJECTIVE: To investigate nuclear volume estimates by the point-sampled int ercepts method in atypical adenomatous hyperplasia (AAH) as compared with n odular hyperplasia and well-differentiated prostatic adenocarcinoma. STUDY DESIGN: The study group consisted of 27 formalin-fixed, paraffin-embe dded, whole-mounted radical prostatectomy specimens that contained foci of nodular hyperplasia, atypical adenomatous hyperplasia and well-differentiat ed adenocarcinoma (Gleason pattern 1 and 2). Representative sections were s elected for stereologic estimation of volume-weighted mean nuclear volume b y the point-sampled intercepts method. On each focus, an average of five fi elds of vision were systematically chosen. RESULTS: The quantitative results indicate an increase in nuclear volume fr om nodular hyperplasia (209 +/- 65 mum(3)) to AAH (237+/-85 mum(3)) and pro state adenocarcinoma (436+/-106 mum(3)). Significant differences were found (F = 39.0, P <.001) with two group comparisons (Scheffe's procedure) betwe en prostate cancer and AAH (P <.001) or nodular hyperplasia (P <.001). The difference between AAH and benign hyperplasia was not significant. CONCLUSION: The results indicate that three-dimensional estimates of the nu clear size discriminate AAH and nodular hyperplasia from well-differentiate d prostate adenocarcinoma. These findings suggest that AAH is probably a hi stologic variant of benign prostatic hyperplasia the exact relationship of which to prostatic adenocarcinoma remains to be determined.