Percutaneous cryoablation of clinical t2 (> 7 cm) renal masses: Technical considerations, complications, and short-term outcomes

Purpose To determine the technical success, safety, and preliminary clinical outcome of percutaneous cryoablation of large (> 7 cm) renal masses. Materials and Methods Twelve patients underwent percutaneous cryoablation for treatment of renal tumors measuring greater than 7 cm (clinical stage II, T2aN0M0) between 2004 and 2013. Median patient age was 75 years (range, 46-84 y), median Charlson comorbidity index was 5 (range, 4-9), and median maximal tumor diameter was 8.4 cm (range, 7.2-9.7 cm). Seven of the 12 patients underwent superselective intraarterial tumor embolization before cryoablation. Technical success, procedural complications, renal function, and oncologic and survival outcomes were evaluated for each patient. Results All cryoablation procedures were technically successful in a single treatment session, with no mortalities at 30 days. Two patients (17%) experienced major complications related to postprocedural hemorrhage. Median change in estimated glomerular filtration rate within 7 days following cryoablation treatment was 11 mL/min (range, 7-14 mL/min). One patient with baseline stage IV chronic kidney disease and a major bleeding complication required temporary dialysis in the periprocedural period. In 11 patients (92%) who had follow-up beyond 3 months after the procedure (mean, 19 mo; range, 4-49 mo), recurrence-free survival and overall survival rates at 2 years were 100% and 91%, respectively. Conclusions Percutaneous cryoablation of large (> 7 cm) renal masses was technically successful, with effective preliminary clinical outcomes. However, major complications are more common with cryoablation of stage T2 tumors than is typically encountered with treatment of smaller stage T1 tumors.