Meta-analysis of RCTs shows mPCNL yields higher single-session stone-free rates than RIRS for medium renal stones

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World journal of urology Published May 24, 2026 Medically reviewed May 24, 2026 Study authors: Alharran Abdullah M, Albloushi Mohammed H, Ali Ahmad M, Aldousari Abdulrahman Hamad, Gadelmawla Ahme… PubMed ↗ DOI ↗ By Dr. Lars van Dijk, PhD · Surgical, Procedural & Diagnostic

Key Takeaway

Consider individualizing RIRS versus mPCNL choice by balancing stone-free rates against invasiveness for medium renal stones.

This meta-analysis of randomized controlled trials compared retrograde intrarenal surgery and miniaturized percutaneous nephrolithotomy for treating medium-sized renal stones ranging from 1 to 3 cm. The analysis pooled data from 4173 patients to assess single-session stone-free rates and overall complication rates as primary outcomes. Secondary outcomes included stone clearance, operative performance, and recovery metrics. The cumulative evidence for single-session stone-free rates was deemed sufficient and conclusive by the authors.

Results indicated that miniaturized percutaneous nephrolithotomy achieved a significantly higher single-session stone-free rate with a relative risk of 0.92 and a 95% confidence interval of 0.88 to 0.96. The p-value was less than 0.001. Conversely, retrograde intrarenal surgery showed a trend toward a lower overall complication rate with a relative risk of 0.79, though the 95% confidence interval of 0.63 to 1.01 and a p-value of 0.057 indicated the difference was not statistically significant. High-grade Clavien-Dindo III-V complication rates were comparable between both techniques.

Operative times were comparable, but retrograde intrarenal surgery required significantly more postoperative auxiliary procedures. Other metrics showed retrograde intrarenal surgery had reduced blood transfusion requirements and smaller hemoglobin drops with shorter hospitalization times. The authors note that findings for overall complication rates should be interpreted cautiously. Practice relevance suggests individualizing the choice between techniques by balancing maximal stone-free rates against procedural invasiveness based on patient characteristics and stone complexity.

Study Details

Study typeMeta analysis

Sample sizen = 4,173

EvidenceLevel 1

PublishedMay 2026

PMID42177692

View Original Abstract ↓

BACKGROUND: The optimal management of medium-sized (1-3 cm) renal stones remains a clinical dilemma, with retrograde intrarenal surgery (RIRS) and miniaturized percutaneous nephrolithotomy (mPCNL) serving as competing minimally invasive options. To overcome the selection bias inherent in previous meta-analyses that included observational data, we aimed to compare the efficacy and safety of both techniques by exclusively analyzing randomized controlled trials (RCTs). METHODS: A systematic literature search of five databases was conducted up to February 2026. Only RCTs comparing RIRS and mPCNL were included. The primary outcomes were the single session stone-free rate (SFR) and overall complication rate. Secondary outcomes included stone clearance-related outcomes, operative performance outcomes, and recovery-related outcomes. Data were pooled using a random-effects model, and trial sequential analysis (TSA) was applied. RESULTS: Thirty RCTs encompassing 4173 patients were included. mPCNL demonstrated a significantly higher single-session SFR compared to RIRS (R.R: 0.92, 95% C.I: 0.88-0.96, p < 0.001). RIRS showed a trend toward a lower overall complication rate although the difference did not reach statistical significance (RR = 0.79, 95% CI: 0.63-1.01; p = 0.057), reduced blood transfusion requirements, smaller hemoglobin drops, and shorter hospitalization times. However, RIRS required significantly more postoperative auxiliary procedures. Operative times and high-grade Clavien-Dindo III-V complication rates were comparable between both techniques. TSA confirmed that the cumulative evidence for single-session SFR was sufficient and conclusive, whereas TSA findings for overall complication rate should be interpreted cautiously. CONCLUSIONS: mPCNL achieves significantly higher SFR than RIRS in the management of 1-3 cm renal calculi. However, RIRS was associated with lower bleeding-related morbidity and shorter hospitalization, although no statistically significant difference was observed in the overall complication rate. Therefore, the choice between RIRS and mPCNL should be individualized, balancing maximal SFR against procedural invasiveness according to patient characteristics and stone complexity.