Cryoablation of small renal tumors in patients with solitary kidneys: initial experience

Introduction. The purpose of this study was to evaluate the role of renal cryoablation in patients with solitary kidneys with the goals of tumor destruction and maximal renal parenchymal preservation. Methods. Eleven patients with single tumors were treated with cryoablation, of which 10 patients had solitary kidneys and 1 had a nonfunctioning contralateral kidney. All procedures were performed via an open extraperitoneal approach; ten tumors were treated with in-situ cryoablation and 1 tumor was treated with cryo-assisted partial nephrectomy. Results. Cryoablation was successfully performed without any preoperative complications. Mean patient age was 62.4 years (range 49-79), tumor location included: 6 (upper pole), 2 (mid-kidney), 3 (lower pole). The mean and median tumor size was 2.6 cm and 2.8 cm (range 1.2-4.3 cm), mean operative time 205 minutes (range 180-270 minutes), blood loss 98.5 ml (range 40-250 ml), and hospitalization 4.6 days (range 3-8 days). Creatinine values included: preoperative 1.43 mg/dL (range 1.2-1.9), postoperative 1.67 mg/dL (range 1.5-2.5), and nadir 1.57 mg/dL (range 1.3-2.1). All patients were followed postoperatively with magnetic resonance imaging for surveillance. At a median follow-up of 43 months, 9 patients had no evidence of recurrence, 1 patient has an enhancing indeterminate area, and 1 patient was lost to follow-up. Conclusion. Intermediate-term results suggest that renal cryoablation offers a feasible alternative for patients that require a maximal nephron-sparing effort with preservation of renal function and minimal risk of tumor recurrence.