TRANSURETHRAL MICROWAVE THERMOTHERAPY IN PATIENTS WITH BENIGN PROSTATIC OBSTRUCTION

The effect of transurethral microwave thermotherapy (TUMT) with Prosta tron in patients with benign prostatic hypertrophy was investigated. T wo hundred and one patients were treated between January 1991 and June 1992 after informed consent was signed. The following examinations we re carried out at screening : interview (including symptom score evalu ation), physical examination (including digital rectal examination), h aematology and blood chemistry (including prostate specific antigen), ECG, chest Xray, kidney, bladder and prostate (transrectal) ultrasound sonography (USS) and uroflowmetry; pressure-flow study was performed in a selected group of patients. All enrolled patients had Madsen symp tom score greater-than-or-equal-to 8 ; peak flow rate less-than-or-equ al-to 15 ml/s and post void residual urine less-than-or-equal-to 200 m l. Patients with obstructive middle lobe of the prostate, any BPH comp lication or any suspicion of prostatic carcinoma were excluded from th e study. Microwave thermotherapy with Prostatron was carried out accor ding to software generation 2.0 (Prostasoft 2.0), the c10 (black) cath eter was used in all patients. Follow-up visits were scheduled at 1 we ek, 1, 3, 6, 12, 18 months after microwave thermotherapy. Overall shor t- and long-term morbidity rates were 6.09 and 2.73 per cent, respecti vely. At 12 months, Madsen score was found to be reduced from 11.7 +/- 4.78 to 4.43 +/- 3.30 ; maximum flow rate (Qmax) was increased from 8. 91 +/- 4.20 to 13.20 +/- 4.86 ; post void residual urine (PVRU) was re duced from 131 +/- 17.6 to 67.40 +/- 34.50. Pressure-flow study showed no modification of the minimal urethral opening pressure (pmuo) at 6 months : from 38.40 +/- 14.00 to 34.20 +/-6.14 cm H2O ; slope value (P /F2) decreased from 2.85 +/- 2.35 to 1.26 +/- 1.17. Increased elastici ty of prostatic urethra was observed after treatment resulting in a sh ift of the linear passive urethral resistance relation (PURR). Best th erapeutic response occurred in patients with mild prostatic obstructio n.