Since August 1990, we used the Thermex-II system to treat prostatism in 220 patients for whom an indication of transurethral prostatectomy was proposed, in 85% by some other urologists and the last 15% by us. The treatment was offered on a clinical research basis, and the patient received large information. No complications other than 10 short-term retentions (2-15 days), mild hematuria and 2 marked prostatic edema were noted. Objective amelioration was seen in 78%, and subjective amelioration was noted in 83%. Only 6 patients needed surgery.