Effect of Transurethral Microwave Thermotherapy

Abstract

Purpose:

To detect morphological changes in the prostate, as depicted with MR imaging, in order to clarify the effects of transurethral microwave thermotherapy (TUMT).

Material and Methods:

Twenty patients with prostatism and a prostatic volume of 30–71 cm³ underwent MR examination before, the day after, and 6 months after treatment. TUMT was carried out with a Prostatron. A method to detect oedematous changes on heavily T2-weighted MR images was developed and used as an indicator of morphological changes.

Results:

The study showed some correlation (r=0.59) between the energy given at TUMT and an increased T2 signal. All patients with increased T2 signal except one were found among those who received the highest amount of energy to the prostate. Of 8 patients, 6 showed a symptomatic response to the treatment and 2 did not. There was a weak statistical correlation (r=0.41) between treatment response and increased T2 signal.

Conclusion:

The study does not support the view that TUMT leads to significant necrosis in the prostate with loss of tissue and retraction. We theorize that the response to TUMT may be caused by a denervation of the prostate.