Optimization of transurethral hyperthermia: number of treatments

The optimal number of transurethral microwave hyperthermia (TUHT) treatments in patients with moderate to severe symptoms of benign prostatic hyperplasia (BPH) is not known. This study was designed to compare TUHT efficacy with the use of three versus six treatments.

In a Phase II prospective trial during a three-month period, 28 poor surgical risk patients with moderate to severe prostatism were randomized to receive three or six TUHT sessions. TUHT treatments were given on an outpatient basis without sedation or anesthesia for sixty minutes at 915 MHz with the temperature controlled on the urethral surface at 45 degrees C.

Subjective improvement was obtained in 7 (50%) patients receiving three TUHT treatments and in 12 (86%) patients receiving six treatments. A greater degree of improvement in total symptom score (P = 0.01) and obstructive (P = 0.01) and irritative (P = 0.04) symptoms was also recorded in the 14 patients receiving six treatments compared to those treated with three TUHT sessions (P = 0.01). A posttreatment improvement in objective study parameters was recorded for both treatment groups. The 14 patients treated with six TUHT sessions, however, showed a better improvement in peak flow rates (51% vs. 8.4%, P = 0.003) and postvoiding residual volume compared to the 14 patients treated with three TUHT sessions (P = 0.10). Treatments were very well tolerated and no clinically significant toxicity was recorded. Of the 9 study patients who failed to respond to treatment, 1 patient was successfully retreated with TURP while 8 patients required an indwelling catheter.

In TUHT in poor surgical risk patients with BPH with the temperature controlled at 45 degrees C, six treatments were superior to three treatments, based on a higher incidence of subjective and objective improvement.