Flexible Ureteroscopy with a Tip-bendable Suction Ureteral Access Sheath Versus Mini-Percutaneous Nephrolithotomy for Treatment of 2–3-cm Renal Stones: Study Protocol for an International, Multicenter, Randomized, Parallel-group, Noninferiority Trial
Wei Zhu, Chu Ann Chai, Jinxiang Ma, Mehmet İlker Gökçe, Nariman Gadzhiev, Jaisukh Kalathia, Kehua Jiang, Xianzhong Duan, Jianwei Cao, Rongpei Wu, Rijin Song, Song Bai, Xuedong Li, Shusheng Liu, Guohua Zeng
Abstract
The aim of our study is to assess whether flexible ureteroscopy with a suction bendable ureteral access sheath is comparable to mini-percutaneous nephrolithotomy in terms of the stone-free rate and perioperative outcomes. Guidelines recommend percutaneous nephrolithotomy (PCNL) for larger renal stones, but advances in flexible ureteroscopy (f-URS) with a tip-bendable suction ureteral access sheath (S-UAS) have prompted further investigation. Our multicenter, international, randomized controlled trial is investigating whether f-URS with S-UAS is noninferior to mini-PCNL (mPCNL) for renal stones of 2–3 cm. The primary objective is the immediate stone-free rate (SFR). Secondary outcomes include the 3-mo SFR, complication rates, surgical time, hospital stay, auxiliary procedures, and improvements in quality of life. A total of 720 patients from 12 urological centers will be randomized to either f-URS with S-UAS or PCNL. Statistical analyses will include intention-to-treat and per-protocol approaches, with specific methods for normally and non-normally distributed data. Subgroup analyses will focus on stone location and lithotripter types. The significance threshold will be set at p < 0.05. The aim of this trial is to generate high-level evidence regarding the noninferiority of f-URS with S-UAS compared to mPCNL for medium-sized renal stones. The trial is registered on ClinicalTrials.gov as NCT06526390.