The aim of this study is to evaluate the mechanisms involved in the apoptosis induced by a treatment of finasteride on benign prostate hyperplasia (BPH). Five sets of patients who need a surgical procedure because of low tract urinary symptoms are randomly attributed to one of five sets of treatment: 0, 7, 14, 21 or 28 days of finasteride treatment before the day of the procedure. Prostate histological fragments are conditioned for molecular and histologic studies.