A Sham Controlled Trial of Transurethral Microwave Therapy with Subsequent Treatment of the Control Group

Abstract

To investigate whether there is a significant placebo component to the improvements seen after 1-session transurethral microwave treatment, 40 patients with significant symptoms of prostatism and unequivocally benign glands were recruited to take part in a sham controlled study. After an active treatment the mean American Urological Association symptom scores improved by 63% (19.2 to 7.1) while after a sham treatment symptom scores improved only marginally (18.8 to 16.2, p < 0.001). Residual volumes decreased by 50% (104 to 52ml.) and flow rates increased by 2.3ml. per second after an active treatment with no improvement after a sham treatment. There was a consistently greater improvement after an active treatment compared to a sham treatment. Patients who had received a sham treatment were then offered an active treatment and showed improvements similar to those in the original actively treated group and much greater than after the original sham treatment. Mean symptom scores decreased from 16.2 to 9.9 (p < 0.004). Residual volumes decreased from 94 to 40 ml. (p < 0.005) and flow rates increased by 1.6ml. per second, while these same criteria had deteriorated after a sham treatment.Side effects were mild and short lived, with no patients reporting sexual dysfunction as a consequence of treatment. Transurethral microwave therapy is an effective well tolerated treatment for select patients with benign prostatic hypertrophy and the placebo effect of treatment is minimal.