High-energy microwave thermotherapy in patients in urinary retention.

Purpose: To study the outcome of high-energy transurethral microwave thermotherapy (TUMT) in patients with obstructive benign prostatic hyperplasia (BPH). Patient and Methods: Between September 1995 and March 1998, patients presenting with urinary retention secondary to BPH were recruited into the study. Their mean age was 67.2 years (range 50-85 years). The mean catheterization time prior to treatment was 3 months (range 15 days-1 year). Among the 200 patients treated during this period, 30 were high anesthesia risk (American Society of Anesthesiologists Class III/IV). The patients were treated in a single 1-hour session using high-energy (Prostatron 2.5) software, the range of energy transmitted being 111.9 to 214.2 kJ (mean 196.3 kJ). Symptoms were scored according to the International Prostatic Symptom Score (IPSS). The mean prostate volume subjected to TUMT was 59 cc (range 40-149.7 cc). The patients were followed every 3 months with measurements of peak flow rate, postvoiding residual urine volume estimation, and IPSS. Results: Of the 200 patients, 33 were lost to follow-up, 155 were responsive (catheter free with physiologically acceptable peak flow rate), and 12 (7%) were nonresponsive. Only 4 patients (2%) experienced deterioration in their flow rates during the follow-up period of 2 years. They underwent transurethral resection. High-energy thermotherapy resulted in irritative voiding complaints in 80% of patients for 2 to 4 weeks. Conclusion: The initial results were encouraging, and the 2-year follow-up has shown appreciable sustainability in the treatment outcome, particularly in patients at high anesthesia risk.