Retrograde intrarenal surgery vs miniaturized percutaneous nephrolithotomy to treat lower pole renal stones 1.5-2.5 cm in diameter.

Aim: To compare the outcomes of retrograde intrarenal surgery (RIRS) and miniaturized percutaneous nephrolithotomy (mini-PCNL) in treating lower pole (LP) renal stones with a diameter of 1.5-2.5 cm.

Methods: A total of 216 patients who underwent mini-PCNL ( = 103) or RIRS = 113) for LP stones with a diameter of 1.5-2.5 cm were enrolled between December 2015 and April 2017 at the Urology Department of Ningbo Urology and Nephrology Hospital.

Results: Significant differences were found in the hospital stay (9.39 ± 4.01 14.08 ± 5.26, < 0.0001) and hospitalization costs (2624.5 ± 513.36 3255.2 ± 976.5, < 0.0001) between the RIRS and mini-PCNL groups. The mean operation time was not significantly different between the RIRS group (56.48 ± 24.77) and the mini-PCNL group (60.04 ± 30.38, = 0.345). The stone-free rates at the first postoperative day (RIRS mini-PCNL: 90.2% 93.2%, = 0.822) and the second month postoperatively (RIRS mini-PCNL: 93.8% 95.1%, = 0.986) were not significantly different.

Conclusion: RIRS and mini-PCNL are both safe and effective methods for treating LP stones with a diameter of 1.5-2.5 cm. RIRS can be considered as an alternative to PCNL for the treatment for LP stones of 1.5-2.5 cm.