Transurethral microwave thermotherapy: How does it work?

Although some authors have proposed that the favorable impact of transureth ral microwave thermotherapy (TUMT) for benign prostatic hyperplasia has onl y a placebo effect, this idea is inconsistent with the findings of a number of sham-controlled clinical trials. Histologic and immunohistochemical stu dies have shown that the nerve fibers in the periurethral tissue are damage d or ablated by TUMT, and it appears that the heat affects the innervation of the smooth muscle cells, Among the nerves damaged are tbe sensory neuron s of the posterior urethra, and this change might reduce the excitatory sig nals from the urethrodetrusor facilitating reflexes. Necrosis and apoptosis within a limited area also have been described. Thus, there is likely more than one basis for the therapeutic effect of TUMT.