Percutaneous nephrolithotomy (PCNL) is recommended as the first-line treatment choice for the management of kidney stones larger than 2 cm. However, tract-related complications have always been a concern, especially in standard PCNL where a larger tract > 24Fr is established. The mini-PCNL technique with smaller tract (≤ 18 Fr) has been introduced to decrease tract related complications. Yet, with a smaller mini-PCNL tract, fragments must be fragmented into smaller pieces before extraction, potentially prolonging the operative time. Moreover, if the outflow of irrigation fluid is insufficient via the smaller tract, the intrarenal pressure (IRP) can build up, leading to pyelovenous backflow and infectious complications - an issue theoretically mitigated by the addition of suction techniques. However, high-level evidence comparing suction mini-PCNL outcomes to standard PCNL is still lacking.
The present multicenter, international, randomized controlled noninferiority trial compares suction mini-PCNL to standard PCNL in the management of 2-4 cm kidney stones. The primary outcomes are the immediate postoperative stone-free rate (SFR) and operative time, while secondary outcomes include the final SFR at 1 month, postoperative pain score, length of hospital stay, postoperative complications, and quality of life.
A total of 960 patients from 20 urological centers will be randomized to receive either suction mini-PCNL or standard PCNL. Intention-to-treat analysis will be performed. For SFR, non-inferiority will be concluded if the lower bound of the 95% confidence interval for the absolute risk difference exceeds - 10%. For operative time, non-inferiority will be concluded if the lower bound of the 95% confidence interval for the mean difference exceeds - 10 min. For all other analyses, a two-sided p-value of < 0.05 will be regarded as statistically significant. Subgroup analyses will be performed to explore potential effect modification by stone location and stone density.
The aim of this trial is to generate high-level evidence regarding the noninferiority of suction mini-PCNL compared to standard PCNL for 2-4 cm renal stones. The trial is registered on ClinicalTrials.gov as NCT05088213.
World journal of urology. 2026 Feb 26*** epublish ***
Wen Zhong, Kehua Jiang, Xuepei Zhang, Chi Ho Leung, Wei Zhu, Zhanping Xu, Guofu Pang, Zhongyi Sun, Fan Cheng, Jin Li, Jie Chen, Yuanwei Li, Houmeng Yang, Shulian Chen, Chuanxun Wu, Rui Jia, Jin Zhu, Jorge Gutierrez-Aceves, Emanuele Montanari, Shabir Almousawi, Iliya Saltirov, Marcin Popiolek, Albert Aquino, Giorgio Mazzon, Simon Choong, Haibo Xi, Steffi Kar Kei Yuen, Guohua Zeng
Department of Urology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China., Department of Urology, Guizhou Provincial People's Hospital, Guiyang, China., Department of Urology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China., SH Ho Urology Centre, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, China., Department of Urology, Foshan Hospital of Traditional Chinese Medicine, The Eighth Clinical Medical College of Guangzhou University of Chinese Medicine, Foshan, China., Department of Urology, Zhuhai People's Hospital, Zhuhai Hospital Affiliated of Jinan University, Zhuhai, China., Department of Urology and Carson International Cancer Center, Shenzhen University General Hospital, Shenzhen, China., Department of Urology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China., Department of Urology, Central Hospital of Xiangtan, Changsha, China., Department of Urology, Jiangxi Provincial People's Hospital, The First Affiliated Hospital of Nanchang Medical College, Nanchang, China., Department of Urology, Hunan Provincial People's Hospital, Changsha, China., Department of Urology, Huamei Hospital, University of Chinese Academy of Sciences, Ningbo, China., Department of Urology, Affiliated Hospital of Zunyi Medical University, Zunyi, China., Department of Urology, The First People's Hospital of Fuquan City, Fuquan, China., Department of Urology, Qiannan Buyi and Miao Autonomous Prefecture Hospital, Duyun, Guizhou Province, China., Department of Urology, the Second Affiliated Hospital of Soochow University, Suzhou, China., Department of Urology, Cleveland Clinic, Cleveland, Ohio, USA., Department of Urology, University of Milan - Fondazione Ca'Granda IRCCS Ospedale Maggiore Policlinico Milano, Milan, Italy., Department of Urology, Sabah Al-Ahmad Urology Centre, Kuwait City, Kuwait., Department of Urology and Nephrology, Military Medical Academy, Sofia, Bulgaria., Department of Urology, Örebro University Hospital, Örebro, Sweden., Department of Urology, Jose R. Reyes Memorial Medical Center, Manila, Philippines., Department of Urology, University College London Hospitals, London, UK., Department of Urology, The First Affiliated Hospital of Nanchang University, Nanchang, China. ., SH Ho Urology Centre, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, China. ., Department of Urology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China. .