Transurethral microwave thermotherapy - Pilot study on the value of the Dornier urowave

TUMT applies high-power microwave energy deep within the lateral prostatic lobe and should lead to a decrease in adenoma volume and destruction of a certain specific cell type involved in outlet obstruction. The aim of the present study was the evaluation of safety and efficacy of TUMT with the Dornier urowave (Germering/Germany) in patients with obstructive benign prostatic hyperplasia (BPH). Between February 1992 and August 1994, 83 patients were enrolled and, according to protocol, received one-hour of TUMT under sedoanalgesia. The surgical risk of these patients was assessed by the ASA-score. Inclusion criteria were IPSS greater than or equal to 15, maximal uroflow less than or equal to 12 ml/sec and endoscopically confirmed absence of urethral stricture, lobes and the absence of an obstructive middle lobe. Microwave energy was 37.8 W, rectal borderline temperature measured 43.5 degrees C and urethral borderline temperature 44.5 degrees C. Energy and temperature were recorded continuously. IPSS, uroflow, residual urine acid PSA as well as intermediate complications were registered at month 1,3, 6, 9 and 12. Results: Residual urine sank by 67% (p < 0.0001) whereas uroflow increased by 43% (p < 0.0001) at month 12. Pressure flow studies (PURR/DURR) did not reveal a statistically significant difference between the pre- and posttreatment situation. However, these studies were difficult as a result of the old age of the patients. Side effects: Therapy was well-tolerated with one exception, side effects were mild and temporary. Because of urinary retention in 21% of the patients, temporary urinary diversion became necessary. 14.6% of the patients required surgery because of increasing symptoms, and indwelling catheter was placed in one patient. 9 patients required permanent care in a foster home or died during follow-up. In summary, the feasability of TUMT in a negatively preselected group of patients due to comorbidity and/or old age has been demonstrated. The cost-effectiveness calculation in these patients is pending.