Outcome of extracorporeal shockwave lithotripsy monotherapy for large renal calculi: effect of stone and collecting system surface areas and cost-effectiveness of treatment.

The treatment options for large renal calculi are controversial. We report on our experience with 65 treatments of renal calculi > 3 cm using extracorporeal shockwave lithotripsy (SWL) monotherapy. We stratified our results according to stone and collecting system surface areas (measured by computer image analyses), stone location, and stone type. The overall success rate of SWL monotherapy was 27% at 3 months. The best stone-free rate (60%) was obtained for stones < 500 mm2 and located primarily within the renal pelvis. The stone-free rate for stones with surface areas > 1000 mm2 was only 8%. None of the cystine stones was treated successfully, whereas 80% of patients with uric acid stones became stone free. We estimated an average cost of $67,048 to render a patient with a large renal calculus stone free using SWL monotherapy. We recommend that other treatment options, such as percutaneous nephrolithotomy, be considered as first-line therapy for large renal calculi.

Transurethral microwave thermotherapy for management of benign prostatic hyperplasia: results of the United States Prostatron Cooperative Study.

The primary objective of the study was to determine the safety and efficacy of transurethral microwave thermotherapy for the treatment of symptomatic benign prostatic hyperplasia. From March to August 1991, 150 patients were entered into a multi-site study and treated with transurethral microwave thermotherapy under a Food and Drug Administration approved protocol. Only patients with symmetrical trilobar or bilobar prostatic hypertrophy, peak flow rate of less than 15 cc per second (on 2 voided volumes of 150 cc or greater) and a total Madsen symptom score of more than 8 were treated. Transurethral microwave thermotherapy was performed with a 20F catheter and 1,296 MHz. microwave antenna for 60 minutes. The mean power achieved for this single session was 32.1 watts, with a mean power at maximum urethral temperature of 41.1 watts. Mean urethral temperature was 44.3C and the mean rectal temperature was 42.2C. The rectal and urethral temperatures were continuously monitored. Mean peak urinary flow rates, Madsen symptom score, post-void residual volume and improvement in motivating symptom to seek treatment were measured at 6 weeks, and 3, 6 and 12 months. Mean peak urinary flow rates improved 33% at 12 months (p < 0.0001). Overall, the mean Madsen symptom score improved 61% (p < 0.0001). The obstructive score and the irritative score improved 67% and 43%, respectively. Of 17 patients 12 (71%) reported improvement in weak stream when that was the motivating symptom to seek treatment. Of 28 men 18 (64%) reported improvement in nocturia, while 11 of 30 (37%) reported improvement in daytime frequency and 12 of 17 (71%) reported improvement in urgency. There was no statistically significant difference in post-void residual volume at 12 months from baseline. The treatment was well tolerated by all patients, and side effects were considered mild and transitory. Our study demonstrates the safety, effectiveness, patient tolerability and durability of transurethral microwave thermotherapy.