Retrograde intrarenal surgery with flexible and navigable suction access sheaths vs mini-percutaneous nephrolithotomy for large upper urinary tract stones: a systematic review and meta-analysis.
OBJECTIVE: To conduct a meta-analysis comparing the efficacy and perioperative outcomes of contemporary flexible and navigable suction access sheath-assisted retrograde intrarenal surgery (FANS-RIRS) against percutaneous nephrolithotomy (PCNL) for the management of large upper urinary tract stones, as despite technological advances in RIRS such as high-powered lasers and FANS that have substantially enhanced its performance, current guidelines continue to recommend PCNL as first-line treatment for renal stones >2cm. METHODS: MEDLINE, Embase, and the Cochrane Library were searched for studies performing direct comparisons of FANS-RIRS against PCNL in adult patients until September 2025. Primary outcomes included stone-free rates (SFRs) and need for ancillary procedures. Secondary outcomes included operative time, length of postoperative hospitalisation, and postoperative complications. RESULTS: A total of 10 studies (three randomised control trials, seven retrospective cohort studies) comprising 2347 patients were included; preoperative stone sizes were predominantly 2-3 cm. All PCNL procedures in the studies included were performed as mini-PCNL. The SFRs for FANS-RIRS were comparable with mini-PCNL across all stone sizes (odds ratio [OR] 0.90, 95% confidence interval [CI] 0.70-1.17) and stones ≥2 cm (OR 0.80, 95% CI 0.60-1.08), with low heterogeneity. Ancillary procedures rates were similar (OR 1.22, 95% CI 0.61-2.44). FANS-RIRS was associated with significantly fewer overall complications, specifically smaller haemoglobin decline, need for transfusion, and shorter hospital stay. However, mini-PCNL demonstrated shorter operative times for stones ≥2 cm. Urosepsis rates were low and similar between both groups. Limitations include predominance of Asian studies, variability of practice, and inclusion of non-randomised studies. CONCLUSIONS: Contemporary FANS-RIRS achieves SFRs comparable to mini-PCNL even for 2-3 cm stones, while offering superior safety profiles and shorter hospitalisation; this supports FANS-RIRS as a viable primary treatment in selected patients.