[Usefulness of bcl-2 expression as a new basal cell marker in prostatic pathology].

INTRODUCTION AND OBJECTIVES The diagnosis of invasive adenocarcinoma of the prostate is often difficult in needle prostatic cores, where, additionally, the assessment of the presence of basal cells has demonstrated to be of paramount importance. Currently, the immunohistochemical expression of 34betaE12 antigen and p63 protein are the most utilized markers. In our study, we analyzed comparatively the expression of 34betaE12, p63, bcl-2 and alpha-methylacyl-CoA racemase in order to evaluate the usefulness of bcl-2 as a new marker of the basal cells in prostatic pathology. METHODS AND RESULTS This study comprises radical prostatectomy specimens from 48 patients which were studied in order to determine the lack of staining of basal cells in invasive tumor areas together with the expression of racemase. Likewise, the presence of basal cells in areas of atrophy, hyperplasia, adenosis, and high-grade prostatic intraepithelial neoplasia (PIN) was also examined. Within the areas of adenosis and PIN a discontinuous pattern of basal cell expression was found in some cases. In 2 out of 48 cases (4,2%) of invasive carcinoma a weak bcl-2 expression without a basal cell distribution was found. Moreover, the expression of bcl-2 in the stromal lymphocytes appeared to be essential as an internal positive control of the technique. CONCLUSIONS In addition to classical markers, we demonstrated the diagnostic value of bcl-2 as a new basal cell marker.