Effectiveness of Flexible Ureterorenoscopy Versus Extracorporeal Shock Wave Lithotripsy for Renal Calculi of 5–15 mm: Results of a Randomized Controlled Trial

Abstract Background Primary flexible ureterorenoscopy (URS) and extracorporeal shock wave lithotripsy (SWL) are treatment options in patients with renal calculi of 5–15 mm. Objective To compare effectiveness, complication rates, and pain scores between primary URS and SWL. Design, setting, and participants Between 2011 and 2016, patients with renal calculi between 5 and 15 mm were randomized to undergo either primary URS or SWL. Outcome measurements and statistical analysis Stone-free rate and size of residual fragments assessed by computed tomography after 3 mo, complications, and pain scores were evaluated. Results and limitations The study was prematurely closed after randomizing 44 patients due to poor accrual. The 3-mo stone-free rate and mean residual stone size were, respectively, 61% and 1.8 mm after URS and 48% and 2.4 mm after SWL. Early post-treatment pain scores were significantly higher after URS than after SWL on day 1 (3.3 vs 1.6, p =  0.02) and day 7 (5.2 vs 3.4, p =  0.04), but were no longer detectable after 3 wk and 3 mo, respectively. One Clavien-Dindo grade II complication was observed after URS (5%) and SWL (4%), while one (4%) grade IIIb complication was observed after SWL. Conclusions URS appears to be associated with higher early post-treatment discomfort, which could be associated with routine postoperative stenting. Owing to premature closure of this trial, the power was insufficient to formally compare URS and SWL; however, the present data might be informative to counsel patients about treatment outcomes and allow future meta-analyses. Patient summary This study was ended prematurely, but it contributes data about efficacy and side effects of different treatment options in patients with renal calculi.