Retrograde intrarenal surgery with flexible and navigable suction ureteral access sheaths vs. percutaneous nephrolithotomy for 2-3 cm kidney stones: Is less ınvasive better?

Introduction: The management of renal stones measuring 2-3 cm remains a clinical challenge, with percutaneous nephrolithotomy (PCNL) traditionally favored over retrograde intrarenal surgery (RIRS) due to higher stone-free rates (SFR); however, advancements in flexible ureteroscopy and the introduction of flexible and navigable suction ureteral access sheaths (FANS-UAS) have expanded the role of RIRS for larger stones. This study compares the efficacy and safety of PCNL vs. FANS-UAS-assisted RIRS for medium-sized renal calculi.

Methods: This retrospective study included 116 patients (50 RIRS, 66 PCNL) with 2-3 cm renal stones treated at a single institution. RIRS was performed using an 11/13 Fr FANS-UAS, while PCNL followed standard techniques. Outcomes assessed included operative time, hospitalization, hemoglobin drop, SFR (defined as no fragments ≥1 mm on three-month computed tomography), and complications (Clavien-Dindo).

Results: Baseline characteristics were comparable between groups (p>0.05). RIRS demonstrated significantly shorter operative times (63.1±11.3 vs. 97.3±15.1 minutes, p<0.001) and hospitalization (28.3±17.9 vs. 81±24.8 hours, p<0.001), with less hemoglobin drop (0.4±0.5 vs. 2.1±1.7 g/dL, p<0.001). SFRs were similar at three months (70% RIRS vs. 74.2% PCNL, p=0.677). PCNL had higher complication rates, including three grade III events (vs. none in RIRS), although not statistically significant (p=0.277).

Conclusions: FANS-UAS-assisted RIRS offers comparable SFRs to PCNL for 2-3 cm stones, with advantages in operative efficiency, hospitalization, and perioperative safety. These findings suggest RIRS as a viable minimally invasive alternative, warranting further randomized trials to validate its role in this setting.