Cost-effectiveness of Retrograde Intrarenal Surgery, Standard and Mini Percutaneous Nephrolithotomy, and Shock Wave Lithotripsy for the Management of 1-2cm Renal Stones

Objective: To perform a cost-effectiveness evaluation comparing the management options for mid-size (1-2cm) renal stones including percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), and shockwave lithotripsy (SWL). Methods: A Markov model was created to compare cost-effectiveness of PCNL, mini-PCNL, RIRS, and SWL for 1-2cm lower pole (index patient 1) and PCNL, RIRS, and SWL for 1-2 cm non–lower pole (index patient 2) renal stones. A literature review provided stone free, complication, retreatment, secondary procedure rates, and quality adjusted life years (QALYs). Medicare costs were used. The incremental cost-effectiveness ratio (ICER) was compared with a willingness-to-pay(WTP) threshold of $100,000/QALY. One-way and probabilistic sensitivity analyses were performed. Results: At 3 years, costs for index patient 1 were $10,290(PCNL), $10,109(mini-PCNL), $5,930(RIRS), and $10,916(SWL). Mini-PCNL resulted in the highest QALYs(2.953) followed by PCNL(2.951), RIRS(2.946), and SWL(2.943). This translated to RIRS being most cost-effective followed by mini-PCNL(ICER $624,075/QALY) and PCNL(ICER $946,464/QALY). SWL was dominated with higher costs and lower effectiveness. For index patient 2, RIRS dominated both PCNL and SWL. For index patient 1: mini-PCNL and PCNL became cost effective if cost ≤$5,940 and ≤$5,390, respectively. SWL became cost-effective with SFR ≥75% or cost ≤$1,236. On probabilistic sensitivity analysis, the most cost-effective strategy was RIRS in 97%, mini-PCNL in 2%, PCNL in 1%, and SWL in 0% of simulations. Conclusion: For 1-2cm renal stones, RIRS is most cost-effective. However, mini and standard PCNL could become cost-effective at lower costs, particularly for lower pole stones.