Flexible ureteroscopy (f-URS) has undergone substantial evolution with the introduction of flexible and navigable suction ureteral access sheaths (FANS), expanding its applicability to larger renal calculi. Although mini-percutaneous nephrolithotomy (mPCNL) remains a standard treatment for 2–3 cm renal stones, uncertainty has persisted regarding whether contemporary f-URS equipped with suction technology can achieve comparable efficacy with improved safety. Recent high-quality evidence now provides important clarity. A large, multicentre randomised trial comparing FANS f-URS with mPCNL for 2–3cm renal stones demonstrated non-inferior immediate stone-free rates with FANS f-URS, with comparable stone clearance at three months and no increase in the need for auxiliary procedures. Importantly, f-URS was associated with consistent perioperative and recovery advantages, including reduced postoperative pain, shorter hospitalisation, faster quality-of-life recovery, and a markedly lower risk of haemorrhagic complications. While operative times were longer with FANS f-URS, procedure duration remained clinically acceptable and must be interpreted in the context of its minimally invasive profile and avoidance of tract-related morbidity. These findings are particularly relevant for patients with multiple or staghorn stones totalling 2–3cm, in whom mPCNL often necessitates multiple percutaneous access tracts, increasing bleeding risk and recovery time. In contrast, f-URS allows access to multiple calyces without renal parenchymal injury. Although successful FANS placement is critical, contemporary miniaturised sheaths and smaller ureteroscopes have substantially improved feasibility, with staged procedures or conversion to mPCNL remaining reasonable fallback strategies. Haemorrhagic complications continue to be a key limitation of percutaneous approaches, even with miniaturised tracts. The superior bleeding profile observed with FANS f-URS reinforces its appeal as a minimally invasive alternative. Nonetheless, these results should be interpreted with recognition of limited follow-up, absence of cost analysis, and performance in high-volume centres with experienced surgeons. Overall, accumulating evidence supports FANS f-URS as a safe and effective alternative to mPCNL for selected patients with 2–3cm renal stones, expanding minimally invasive treatment options while prioritising recovery and quality of life.
FANS f-URS with mPCNL for 2–3cm renal stones
Reviewed by Asif H Ansari
Flexible ureteroscopy with a flexible and navigable suction ureteral access sheath versus mini-percutaneous nephrolithotomy for treatment of 2-3cm renal stones: an international, multicenter, randomized, noninferiority trial.
