Cryoablation for Endophytic Renal Cell Carcinoma: Intermediate-Term Oncologic Efficacy and Safety

PURPOSE: To evaluate the efficacy and safety of laparoscopic renal cryoablation (LRC) of small endophytic renal cell carcinoma, for which surgical treatment is technically difficult. MATERIALS AND METHODS: We enrolled patients with endophytic tumors from a prospectively collected database of 45 renal tumors in 39 patients who had undergone LRC from June 2005 to May 2009. An endophytic tumor was defined as less than 40% of the lesion extending off the surface of the kidney. We evaluated surgical and oncological outcomes. RESULTS: Among the treated tumors, 17 tumors (37.8%) were defined as endophytic tumors and 15 tumors from 14 patients were confirmed as renal cell carcinoma (RCC) in the pathologic examination of the tissue biopsy that was conducted at the time of LRC. The mean American Society of Anesthesiologists (ASA) score of the whole patient group was 2.9 (range, 1-4), and 85.7% (12/14) of the patients had an ASA physical status score over 3. The mean tumor size was 2.8 cm (range, 1.7-3.7 cm). The layout of the cryoprobe was carefully planned preoperatively on the basis of radiologic evaluation in all tumors. Multiple cryoprobes (mean, 3.2; range, 2-5) were used. No major complications, including open surgical conversion and nephrectomy due to bleeding, occurred. No patient experienced clinical symptoms of collecting system injuries. During the mean follow-up of 32.6 months (range, 12-51 months), radiologic evidence of tumor recurrence was found in one patient (6.7% for RCC). With the exception of this patient, all other patients have remained free of recurrence or metastasis, as determined by periodic radiologic workups. CONCLUSIONS: In this series of patients with intermediate-term follow-up, LRC for endophytic renal cell carcinoma showed acceptable oncological and surgical outcomes without sequelae in the collecting system.