Renal functional outcomes in patients undergoing percutaneous cryoablation or partial nephrectomy for a solitary renal mass

Objectives: To compare renal functional changes after percutaneous cryoablation (PCA) or partial nephrectomy (PN). Patients and Methods: Patients who underwent PCA or PN for a solitary renal mass at a single institution were identified (2003–2013). Estimated glomerular filtration rates (eGFRs) were calculated at baseline, discharge, and at the 3-month follow-up using the Chronic Kidney Disease Epidemiology Collaboration equation. Changes in renal function were compared between groups using 1:1 propensity score (PS) matching, adjustment for PS quintile, and inverse probability weighting (IPW). Results: There were 2 040 procedures available for the PS analyses, including 448 PCA and 1 592 PN. After PS adjustments, there were no significant differences in baseline clinical features between PCA and PN patients. In the PS-matched analysis, the change in eGFR from baseline to discharge for PCA and PN patients was −3.1 and −1.1 mL/min/1.73 m², respectively (P = 0.038), with percentage changes of −4.5% and 0% respectively (P = 0.006). From baseline to the 3-month follow-up, the absolute change in eGFR for PCA and PN patients was −4.3 and −2.1 mL/min/1.73 m², respectively (P = 0.008), and the percentage change was −6.1% and −2.4% respectively (P = 0.005). Similar results were obtained after adjusting for PS quintiles and in the IPW analysis. Importantly, the rate of chronic kidney disease stage progression at the 3-month follow-up was similar between the groups (21% vs 18%). Conclusions: Our results confirm that both PCA and PN have a minor impact on renal function. While we observed a statistically greater decline in eGFR after PCA compared with PN, both approaches result in excellent preservation of renal function.