TREATMENT OF BENIGN PROSTATIC HYPERPLASIA WITH 5-ALPHA-REDUCTASE INHIBITOR - MORPHOLOGICAL-CHANGES IN PATIENTS WHO FAIL TO RESPOND

Aims-To describe the prostatic adenectomy specimens of six patients wi th symptomatic benign prostatic hyperplasia (BPH) who failed to respon d to long term treatment with a 5-alpha-reductase inhibitor, finasteri de. Methods-Histological sections from six cases of BPH who had been t reated with finasteride were investigated. Five patients were prescrib ed 5 mg finasteride daily for six months and one patient 5 mg daily fo r 12 months. The patients underwent adenectomy as their urethral obstr uction failed to resolve. Twenty cases of untreated BPH served as cont rols. Results-In patients taking finasteride for six months the prosta tic adenectomy specimens showed a reduction in the size of the prostat e and an increase in the stroma:epithelial and stroma:lumen ratios com pared with controls. The size of the ducts and acini was not as unifor m as in the controls. In particular, some ducts and acini were still l ined by a bistratified epithelium similar to that found in controls bu t lacked undulations at the epithelial border; other ducts/acini were atrophic. Some scattered clusters of small acini with a focally fragme nted basal cell layer were observed in two of the five treated cases. One prostatic adenectomy specimen, from the patient treated for one ye ar, showed atrophy and diffuse transitional cell metaplasia. At the pe riphery of the transition zone, there was a complex intra-acinar papil lary-cribriform proliferation of clear cells without nuclear atypia, s imilar to clear cell papillary hyperplasia. The periurethral region sh owed stromal nodules in both patients and controls. Conclusions-Morpho logical evaluation of finasteride treated BPH showed changes in the lo bules of the transition zone, but not in the periurethral stroma.