Category: Clinical Stones: Outcomes
Introduction & Objective :
There are no published randomised studies comparing extracorporeal shock wave lithotripsy (SWL), ureterorenoscopy (URS) and percutaneous nephrolithotomy (PCNL) as treatments for 10-20mm renal stones. We have conducted a pilot study to assess the practicality of a sufficiently powered randomised controlled trial.
All adult patients with a maximum stone diameter of 10-20mm on CT scan were eligible for enrolment. Patients were randomised to SWL, URS or PCNL. Treatments were carried out using standard protocols – all SWL conducted without anaesthesia, URS with Holmium:YAG laser dusting and PCNL in the modified supine position. Repeat or alternative treatments were performed as clinically appropriate until the patients were considered stone free. All patients had a post-treatment CT scan to assess stone free rate (SFR). Images were reviewed by a radiologist blinded to treatment. Data collected included pre-treatment stone size and Hounsfield units, pre-/post-treatment global health scores, number/duration of treatments, complications and SFR. Ethical approval was obtained. Data were analysed using Kruskal-Wallis and Chi-square tests.
Thirty one patients were randomised; 11 treated with URS and 10 each for SWL and PCNL. There were no significant differences in age, sex and stone size/position between the groups. SFR were 60%, 55% and 80% for SWL, URS and PCNL respectively (p=0.33). PCNL patients received significantly fewer procedures (median 1, range 1-3) than both SWL (median 2, range 1-5) and URS (median 2, range 1-3) (p=0.015) with an overall similar stay in hospital. Overall complications were more common with SWL (50%), compared to 20% for PCNL and 9% URS (p= 0.019) and the only complications greater than Clavien Grade 1 were following SWL (steinstrasse in 30%).
PCNL achieves the highest SFR with the lowest number of procedures, with a comparable overall length of hospital stay to URS and SWL. URS offers the best combination of minimal morbidity and SFR though patients frequently require ureteric stenting with associated stent-related symptoms. We share the concerns of others that “stone-dusting” techniques may result in incomplete stone clearance. The results of SWL for renal stones ³10mm are unsatisfactory and the findings suggest that this should not be a recommended treatment for this group of patients. In view of these findings the larger powered study will exclude SWL and compare URS to PCNL.
John Bailie– Monash Health, Melbourne, Melbourne, Victoria, Australia
Shekib Shahbaz– Melbourne, Victoria, Australia
Ivor Berman– Melbourne, Victoria, Australia
Matthew Hong– Melbourne, Victoria, Australia
Philip McCahy– Melbourne, Victoria, Australia