TRANSURETHRAL MICROWAVE THERMOTHERAPY FOR MANAGEMENT OF BENIGN PROSTATIC HYPERPLASIA - RESULTS OF THE UNITED-STATES PROSTATRON COOPERATIVE STUDY

The primary objective of the study was to determine the safety and eff icacy of transurethral microwave thermotherapy for the treatment of sy mptomatic benign prostatic hyperplasia. From March to August 1991, 150 patients were entered into a multi-site study and treated with transu rethral microwave thermotherapy under a Food and Drug Administration a pproved protocol. Only patients with symmetrical trilobar or bilobar p rostatic hypertrophy, peak flow rate of less than 15 cc per second (on 2 voided volumes of 150 cc or greater) and a total Madsen symptom sco re of more than 8 were treated. Transurethral microwave thermotherapy was performed with a 20F catheter and 1,296 MHz. microwave antenna for 60 minutes. The mean power achieved for this single session was 32.1 watts, with a mean power at maximum urethral temperature of 41.1 watts . Mean urethral temperature was 44.3C and the mean rectal temperature was 42.2C. The rectal and urethral temperatures were continuously moni tored. Mean peak urinary flow rates, Madsen symptom score, post-void r esidual volume and improvement in motivating symptom to seek treatment were measured at 6 weeks, and 3, 6 and 12 months. Mean peak urinary f low rates improved 33% at 12 months (p < 0.0001). Overall, the mean Ma dsen symptom score improved 61% (p < 0.0001). The obstructive score an d the irritative score improved 67% and 43%, respectively. Of 17 patie nts 12 (71%) reported improvement in weak stream when that was the mot ivating symptom to seek treatment. Of 28 men 18 (64%) reported improve ment in nocturia, while 11 of 30 (37%) reported improvement in daytime frequency and 12 of 17 (71%) reported improvement in urgency. There w as no statistically significant difference in post-void residual volum e at 12 months from baseline. The treatment was well tolerated by all patients, and side effects were considered mild and transitory. Our st udy demonstrates the safety, effectiveness, patient tolerability and d urability of transurethral microwave thermotherapy.