Lower-energy thermotherapy in the treatment of benign prostatic hyperplasia: long-term follow-up results of a multicenter international study

The purpose of the present study was to evaluate the long-term results of l ower-energy transurethral microwave thermotherapy (TUMT) and to determine p redictors for a favorable treatment outcome in an international multicenter study. A total of 1092 patients treated between April 1990 and September 1 993 in 6 different centers in different countries were evaluated. All patie nts were treated in a nonblinded, noncontrolled fashion with the Prostatron thermotherapy device using the lower-energy treatment protocol Prostasoft 2.0. Collected data included voiding parameters, Madsen symptom scores, ret reatments, types of retreatment, and dates of retreatment. Instrumental ret reatment served as the end point for further evaluation. The average age of our patients was 67 years. At baseline the average uroflow rate was 8.7 ml /s. After treatment the improvement in uroffow was 2-3 ml/s. This was maint ained for up to 5 years after treatment for the patients remaining in follo w-up. The overall improvement in the Madsen symptom score was 5-6 points fo r these patients. There was no significant difference between the different centers. During follow-up, however, the number of patients remaining in fo llow-up decreased rapidly. The absolute instrumental retreatment rate appea red to be 26%; however, when patients no longer in follow-up were taken int o account, the calculated retreatment rate was 39.6% (Kaplan-Meier survival analysis). Patients undergoing retreatment were younger at baseline and ha d a higher Madsen score, a bigger prostate, and a greater postvoid residual . No major complication was seen. Lower-energy TUMT gives a sustained objec tive and subjective improvement in patients with moderate symptoms and a lo w-grade bladder outflow obstruction. Patients with bigger prostates, severe symptoms, low rates of maximal uroflow, and large residuals are prone to h ave a higher degree of prostatic obstruction and are not the ideal candidat es for this treatment. The absolute instrumental retreatment rate after 5 y ears was 26%. Moreover, no significant international difference in treatmen t outcome was found.