Two hundred consecutive patients with presumed localized prostate cancer had radical prostatectomy alone (n = 119) or were treated for an average period of 3 months with combination therapy using the antiandrogen flutamide and one luteinizing hormone-releasing hormone (LHRH) agonist (Lupron or Zoladex). The positive margins decreased from 35.3% in the group undergoing prostatectomy alone to 11.5% in the group of men who received combination therapy before radical prostatectomy. In 41 apical tumors, the incidence of positive margins decreased from 50% in the control group to 18.6% in the combination therapy group. In stage C disease, the incidence of positive tumor showed a tendency to decrease with the extended duration of endocrine treatment with a rate of 37.5% after 3 months and 16.7% after 6 months. Whether the decreased incidence of positive surgical margins will all translate into prolonged survival remains to be verified by long-term follow-up of these patients. However, the initial results obtained in the present study are very encouraging.