Clinical sequelae of radiographic iceball involvement of collecting system during computed tomography-guided percutaneous renal tumor cryoablation: Warlick CA, Lima GC, Allaf ME, Varkarakis I, Permpongkosol S, Schaeffer EM, Kavoussi LR, Jarrett TW, Solomo

Objectives aneous renal tumor cryoablation is being evaluated as a treatment option for small renal tumors. However, when tumors are located centrally, involvement of the collecting system by the radiographic iceball can occur. We reviewed our series of computed tomography (CT)-guided percutaneous renal tumor cryoablation to identify those cases in which there appeared to be involvement of the collecting system by the radiographic iceball and to determine any clinical sequelae of such involvement. s pective review of the medical records identified 6 patients who had undergone CT-guided percutaneous renal tumor cryoablation with evidence of collecting system involvement. Measurements of the tumor size, size of the radiographic iceball, and the size of the immediate postprocedure “cryozone” (region of apparent treatment on contrast-enhanced CT) were obtained from the preprocedure, intraprocedure, and immediate postprocedure CT scans. Follow-up imaging was obtained beginning at 3 to 6 months. s tients were identified who met the inclusion criteria and had at least 3 months of documented follow-up. Despite the apparent involvement of the collecting system during the cryoablation procedure, no patient developed clinical signs or symptoms or radiographic evidence of a urine leak or fistula formation. Furthermore, no evidence of ureteral narrowing or stricture formation has been found to date, with a mean follow-up of 167.7 days (range 90 to 288). sions erved no clinically appreciable urine leaks despite what appeared to be obvious involvement of the collecting system by the radiographic iceball. However, care should be exercised to avoid this insult when possible until additional research has confirmed its safety.