Comparison of safety and efficacy of negative pressure aspiration assisted retrograde intrarenal surgery and traditional percutaneous nephrolithotomy in the treatment of upper urinary tract stones larger than 2cm: a systematic review and meta-analysis.

Background: Percutaneous nephrolithotomy (PCNL) is widely regarded as the first-line treatment for upper urinary tract stones larger than 2 cm, as recommended by major urological associations. However, a growing body of research highlights the safety and effectiveness of retrograde intrarenal surgery (RIRS) for managing stones of this size in the upper urinary tract, especially with the advent of suction-assisted techniques in RIRS. This study aims to systematically evaluate the safety and efficacy of negative pressure aspiration-assisted retrograde intrarenal surgery (NPAA-RIRS) in comparison to traditional PCNL.

Method: Eligible studies were found by searching the PubMed, Embase, Web of Science and the CNKI databases for relevant reports published until July 2024. Outcome measures included initial and final stone-free rate (SFR), secondary operation, operation time, hemoglobin level reduction, blood transfusion, interventional embolization, postoperative hospital stay, complications. The assessment of publication bias was conducted using a funnel plot. Ten studies from nine articles were included, involving 1,259 patients.

Results: NPAA-RIRS group showed lower hemoglobin level reduction (WMD = - 1.31, 95% CI [-1.64, - 0.99], P < 0.001), less blood transfusion (RR = 0.15, 95% CI [0.05, 0.50], P = 0.002), shorter postoperative hospital stay (WMD: - 1.93, 95% CI [-2.54, - 1.32], P < 0.001), lower Clavien-Dindo I-II complication rate (RR: 0.51, 95% CI [0.38, 0.67], P < 0.001), and lower overall complication rate (RR = 0.52, 95% CI [0.40, 0.68], P < 0.001) compared to the PCNL group. The PCNL group had shorter operation time (WMD = 0.68, 95% CI [0.22, 1.13], P = 0.003), higher initial SFR (RR = 0.87, 95% CI [0.83, 0.92], P < 0.001), and lower rate of secondary operation (RR = 2.51, 95% CI [1.52, 4.12], P < 0.001) compared to the NPAA-RIRS group. There were no statistically significant differences between the two groups in interventional embolization (RR = 0.28, 95% CI [0.06, 1.33], P = 0.11), final SFR (RR = 0.98, 95% CI [0.94, 1.01], P = 0.740), and Clavien-Dindo III-IV complication rate (RR: 0.65, 95% CI [0.28, 1.51], P = 0.316).

Conclusion: For upper urinary tract stones larger than 2 cm, both NPAA-RIRS and PCNL are equally safe and effective, achieving comparable final SFR. NPAA-RIRS offers advantages in terms of reduced complications, whereas PCNL shows benefits in shorter operation times and a lower likelihood of requiring secondary procedures. Clinicians can therefore select the most suitable approach based on individual patient circumstances.