Percutaneous cryoablation of larger renal masses can be performed with high technical success and low complication rates, according to researchers.
Grant D. Schmit, MD, and colleagues at Mayo Clinic in Rochester, Minn., studied 108 patients with 110 renal masses 3 cm or more in diameter (the average maximal tumor diameter was 4.1 cm) treated with cryoablation. The technical success rate was 97% (107 of 110 tumors).
The three technical failures all resulted from incomplete cryoablation of the deepest margin of a centrally located renal tumor. Nine severe adverse events occurred in six patients, for an 8% major complication rate. No procedural-related deaths occurred. In addition, the investigators found no evidence for local tumor recurrence in any patient with follow-up contrast-enhanced computed tomography or magnetic resonance imaging obtained three months or longer from the time of ablation. Follow-up in these patients averaged 15 months (range 3-42 months).
The findings were published in the Journal of Endourology (2010;24:1255-1262), where the authors cautioned: “Extra scrutiny is needed during cryoablation of central renal masses to make sure the ablation zone extends to include the deepest margin of the tumor.”