Radiofrequency ablation versus nephron-sparing surgery for small unilateral renal cell carcinoma: cost-effectiveness analysis.

PURPOSE

To evaluate the relative cost-effectiveness of percutaneous radiofrequency (RF) ablation versus nephron-sparing surgery (NSS) in patients with small (<or=4-cm) renal cell carcinoma (RCC), given a commonly accepted level of societal willingness to pay.

MATERIALS AND METHODS

A decision-analytic Markov model was developed to estimate life expectancy and lifetime costs for 65-year-old patients with a small RCC treated with RF ablation or NSS. The model incorporated RCC presence, treatment effectiveness and costs, and short- and long-term outcomes. An incremental cost-effectiveness analysis was performed to identify treatment preference under an assumed $75,000 per quality-adjusted life-year (QALY) societal willingness-to-pay threshold level, within proposed ranges for guiding implementation of new health care interventions. The effect of changes in key parameters on strategy preference was addressed in sensitivity analysis.

RESULTS

By using base-case assumptions, NSS yielded a minimally greater average quality-adjusted life expectancy than did RF ablation (2.5 days) but was more expensive. NSS had an incremental cost-effectiveness ratio of $1,152,529 per QALY relative to RF ablation, greatly exceeding $75,000 per QALY. Therefore, RF ablation was considered preferred and remained so if the annual probability of post-RF ablation local recurrence was up to 48% higher relative to that post-NSS. NSS preference required an estimated NSS cost reduction of $7500 or RF ablation cost increase of $6229. Results were robust to changes in most model parameters, but treatment preference was dependent on the relative probabilities of local recurrence after RF ablation and NSS, the short-term costs of both, and quality of life after NSS.

CONCLUSION

RF ablation was preferred over NSS for small RCC treatment at a societal willingness-to-pay threshold level of $75,000 per QALY. This result was robust to changes in most model parameters, but somewhat dependent on the relative probabilities of post-RF ablation and post-NSS local recurrence, NSS and RF ablation short-term costs, and post-NSS quality of life, factors which merit further primary investigation.