Long-term comparative outcomes of partial nephrectomy and cryoablation in patients with solitary kidneys: a single-center analysis.

Abstract

Patients with solitary kidneys are amenable to postoperative acute kidney injury (AKI) after PN. We compared the functional and oncological outcomes of cryoablation (CA) and PN in patients with a solitary kidney and a cT1a renal mass. From a single-institution series, we analyzed 74 patients (31 PN, 43 CA) with a solitary kidney who underwent treatment for a cT1a renal mass. The functional outcomes were AKI and estimated glomerular filtration rate (eGFR) preservation. Oncological outcomes were recurrence and death. Linear mixed-effects and logistic regression models were used for functional outcomes analysis, whereas oncological outcomes were analyzed using the Kaplan-Meier method. Median follow-up was 63.9 months. PN group had lower median age (59 years vs. 68, P<0.001) and larger median tumor size (2.80 cm vs. 2.0, p =0.003). AKI was more common in the PN group on postoperative day 1 (58% vs. 2.8%, P<0.001). However, only one patient in the PN group required temporary dialysis in the perioperative period. eGFR preservation was similar at postoperative 3 months (89% vs. 90%, P=0.083), or 12 months (85% vs. 94%, P=0.2) follow-up. CA group had higher recurrence rate (29% vs. 3.2%, P=0.005), and worse recurrence-free survival (P=0.027). Overall survival (OS) was comparable (P=0.31). In a solitary kidney setting, CA is associated with a lower risk of AKI at postoperative day 1 compared to PN. Functional outcome is comparable upon longer follow-up. The local recurrence rates are significantly higher in the CA group with no significant difference in OS.