Retrograde intra renal surgery versus percutaneous nephrolithotomy for renal stones >2 cm. A systematic review and meta-analysis.

Introduction: The recent advances in technology and miniaturization of endoscopic devices have permitted the use of retrograde intra renal surgery (RIRS) to treat large and complicated kidney stones as first line therapy in alternative to percutaneous nephrolithotomy (PCNL). Systematically review the efficacy and safety of RIRS for large renal stones over 2 cm versus the current gold standard, the percutaneous nephrolithotomy.

Evidence acquisition: A large search was effected in PubMed, Cochrane Library, Embase, Ovid and Scopus regarding the treatment of renal stones over 2 cm with RIR S versus PCNL. Articles not in English and not regarding adult population were excluded. The retrieval time included a time span from 2000 to 2019. All clinical trials were further evaluated about quality and references. The eligible studies were included and analysed with RevMan 5.2 Software.

Evidence synthesis: Two randomized and nine non-randomized studies were included for a total of 1618 patients involved. Our meta-analysis showed no difference in SFR (RR =0.92, 95% CI : 0.86-0.99, P=0.03) and in mean operation time (WMD=6.34 min, 95% CI : -4.98 to 17.65, P=0.27) while shorter hospital stay was reported for RIR S (WMD=-2.15 days, 95% CI: -3.04 to -1.25, P≤0.00001). We reported moreover lower Hb drop (WMD=-0.83 g/dL, 95% CI: -1.20 to -0.45, P≤0.00001) and complications rate in favor of RIRS (RR=0.88, 95% CI: 0.71-1.09, P=0.23).

Conclusions: RIRS is challenging PCNL for the treatment of large renal stones over 2cm, becoming a safe and effective alternative with a comparable stone free rate, lower complication rate and lower hospitalization time. It is, however, of the uttermost importance to share the treatment decision with the patient due to the possibility of requiring multiple RIR S session to completely clear larger stone burdens.