CIO 2021-39 Efficacy and Safety of Cryoablation in the Treatment of Renal Cell Carcinoma

Purpose: Management of small renal cell carcinoma (RCC), specifically clinical T1a RCC, includes a variety of treatment options. However, many of the studies supporting these options are retrospective reviews of a single institution. We present the results of a rigorous, high-quality prospective registry collecting comprehensive data from multiple institutions and experts on the efficacy of cryoablation for the treatment of renal lesions.

Material and Methods: TRACE (Tracking Renal Tumors After Cryoablation Evaluation) is a multicenter, prospective, observational, open-label, registry study of patients with an enhancing renal mass suspicious for malignancy. Patients were treated with cryoablation and subsequently followed for five years.

Results: Over a 6-year period, seven centers enrolled and treated 250 patients with cryoablation. 246 patients with 252 lesions met inclusion criteria. Of those, 145/246 (58.9%) patients with 146 lesions have biopsy-proven RCC. Long-term analysis is ongoing. At the time of the interim analysis, the median follow-up was 42.4 months (0.03-78.29). Overall median lesion size was 2.5 cm. Cryoablation was completed in 245/246 (99%) cases, with 99 procedures performed laparoscopically, 146 percutaneously, and one with an open procedure. There were 42 treatment-related adverse events and 11 serious adverse events totaling 53 adverse events in 40/246 (16.3%) patients. Of these adverse events, 11.3% (6/53) were Clavien-Dindo class III, with no class IV or V events. Only minimal change in renal function was noted in the 12-month period post treatment. The median estimated glomerular filtration rate decreased 3.85 mL/min with a median increase in creatinine of 0.06 mg/dL. The 36-month Kaplan-Meier estimate of time to recurrence, disease specific survival and overall survival for the RCC population was 94.8%, 100% and 91.9%, respectively.

Conclusions: This rigorous, multicenter prospective study provides high-quality, reproducible evidence supporting the efficacy of cryoablation as a primary treatment for clinically suspicious renal masses.