Simultaneous Bilateral Percutaneous Nephrolithotomy: Is It Cost-Effective?

Objective

To compare the cost-effectiveness of simultaneous vs staged percutaneous nephrolithotomy (PCNL) during treatment of patients with large, bilateral stone burden.

Methods

A decision-analytic Markov model was used to assess the cost-effectiveness of simultaneous and staged PCNL for large, bilateral stone burden. Model probabilities and outcomes for index procedures were drawn from a large-volume, single-center cohort. Primary outcomes included costs from a Medicare standpoint with the addition of operative time, length-of-stay costs, effectiveness (quality adjusted life years, QALYs), and incremental cost-effectiveness ratios with a willingness-to-pay threshold of $100,000/QALY.

Results

At 1 year following the index procedure, costs per patient were $52,585 and $61,687 for simultaneous and staged PCNL, respectively. In addition to being less costly, simultaneous PCNL resulted in slightly higher QALYs (0.982) compared to staged PCNL (0.977). On one-way sensitivity analyses, staged PCNL became cost-effective if the stone-free rate increased from 56% to 88% (40% greater per renal unit relative to simultaneous PCNL) or the cost of unilateral PCNL decreased approximately 50% to $4699 ($16,266 less than simultaneous PCNL).

Conclusion

Even when assuming a modest reduction in stone-free rate and slightly higher major and minor complication rates at index procedure, simultaneous bilateral PCNL was both less costly and more effective at 1 year follow up relative to staged bilateral PCNL. This offers further support of simultaneous bilateral PCNL in the proper clinical setting.