Feasibility of Computed Tomography-guided Percutaneous Renal Cryoablation Under Local Anesthesia: A Single Center...

To survey the safety and efficacy of percutaneous cryoablation for renal tumors under local anesthesia and pain control by using the -40°C lethal isotherm of the ice ball to cover the tumor margin as well as the coaxial cryoablation technique.

All procedures were performed between February 2014 and November 2021 with computed tomography (CT) guidance. All tumors were ablated by following the aforementioned plan, according to which tumor margins were covered by the -40°C lethal isotherm. Hydrodissection and coaxial cryoablation were performed in some cases to avoid organ injury and massive bleeding. 2% xylocaine was used for local anesthesia and 50 mg of pethidine (meperidine) was injected intramuscularly for pain control and sedation. The complications were evaluated and the Kaplan-Meier method was used to estimate local recurrence-free survival (LRFS).

Sixty-five tumors [49 renal cell carcinomas (RCC) and 16 angiomyolipomas] were ablated in 55 patients (median Charlson Comorbidity Index=5.0). Local recurrence occurred in three of the 49 RCC cases. Two received a second cryoablation. LRFS at three and five years were both 91%. LRFS at three and five years reached 100% in tumors <3 cm. A large tumor (≥3 cm) was observed in the recurrence group. Hemorrhage was the most common complication (76.9%). Two patients who needed blood transfusion did not receive coaxial cryoablation. Three (4.6%) major complications (Clavien-Dindo grade ≥3) occurred.

By using -40°C as the pre-plan tumor coverage, with the aid of coaxial cryoablation and multiplanar reconstruction method, CT-guided percutaneous renal cryoablation under local anesthesia is a safe and effective procedure in patients with many comorbidities.