Intermediate to Long-Term Clinical Outcomes of Percutaneous Cryoablation for Renal Masses

Purpose The purpose of this study was to evaluate the effectiveness and adverse outcomes of percutaneous cryoablation (CA) for treatment of renal masses in a large cohort of patients. Materials and Methods This retrospective analysis included 299 CA procedures (297 masses in 277 patients) performed between July 2007 and May 2018 at a single institution. The mean patient age was 66.1 years (range, 30–93 years) with 65.8% being male. A total of 234 (78.8%) masses were biopsy-proven renal cell carcinoma (RCC). The mean maximal tumor diameter was 2.5 cm (range, 0.7–6.6 cm). Efficacy was assessed only for ablations of biopsy-proven RCC, whereas the evaluation of adverse events and renal function included all masses. Complications were graded according to the Society of International Radiology classification. Results Major complications occurred in 3.0% of procedures (n = 9), none of which resulted in death or permanent disability. The mean imaging follow-up period was 27.4 months (range, 1–115) for the 199 RCC patients (204 ablated tumors) with follow-up imaging available. Complete response on initial follow-up imaging at mean 4.2 months (range, 0.3–75.6) was achieved in 195 of 204 tumors (95.6%) after a single session and in 200 of 204 tumors (98.0%) after 1 or 2 sessions. Of the RCC patients achieving complete response initially, local recurrence during the follow-up period occurred in 3 of 200 tumors (1.5%). Metastatic progression occurred in 10 of 193 (5.2%) RCC patients without prior metastatic disease during follow-up. Conclusions CA for renal masses is safe and remains efficacious through intermediate- and long-term follow-up.