Frequency of focal prostatic carcinoma and atypical glandular proliferations in 1,000 needle prostatic biopsies

Introduction. With the routine use of prostatic specific antigen blood determination, sextant biopsies and immunohistochemical studies, focal carcinomas and atypical glandular proliferations (AGP), limited to isolated histologic fields are being detected more frequently. The recognition of these lesions is important since many of them correspond to potentially curable cancers or to benign lesions that mimic carcinoma. Material and methods. 11000 consecutive prostatic biopsies performed during the period of 2000-2007 were reviewed. 42 focal prostatic lesions were retrieved. We reassessed the original HE slides. Additional histologic sections and immunohistochemical studies were performed in those cases with uncertain diagnoses in order to clarify the nature of the lesions. Results. Thirteen (1.3%) lesions corresponded to focal carcinomas and 29 (2.9%) to AGP. Immunohistochemical studies and the analysis of additional histologic sections allowed the classification of 17 cases of AGP into specific categories (prostatic adenosis, atrophy, atypical basal cell hyperplasia and seminiferous ducts). Only three of the 13 patients diagnosed with focal carcinomas were subjected to radical prostatectomy in our institution, all of them had disease limited to the prostatic gland. Of the 29 AGP, additional biopsies were taken in four cases and in one of them prostatic carcinoma was the final diagnosis. Conclusions. A significant number of AGP biopsies could be sub classified in to specific diagnostic categories with the use of immunohistochemical studies and additional HE levels. The frequency of focal carcinoma and AGP in our material was similar to other series, however in many of the AGP cases additional biopsies were not performed despite its high predictive value for carcinoma. Increase use of follow-up biopsy procedures is needed in order to detect early potentially curable lesions.