Short-term efficacy of temperature-based radiofrequency ablation of small renal tumors

OBJECTIVES: To present our experience using radiofrequency ablation (RFA) for the treatment of small renal tumors. Our objective was to assess the short-term (1 to 3 years) oncologic efficacy of RFA. METHODS: Consecutive renal tumors treated since May 2001 with a minimal follow-up of 6 months were included. Patients were treated with a temperature-based radiofrequency generator and were followed up with serial imaging at 6 weeks, 3 and 6 months, and every 6 months thereafter. RESULTS: A total of 109 small renal tumors (91 patients) were treated with computed tomography-guided percutaneous RFA (n = 63) or laparoscopic RFA (n = 46). The mean tumor size was 2.4 cm (range 0.8 to 4.7). The initial ablation was successful in 107 (98%) of 109 tumors. The two incomplete ablations were successfully re-ablated. Of the 60 patients with at least 1 year of follow-up, 60% had biopsy proven renal cell carcinoma (an additional 24% had no tissue diagnosis). In this group, one local recurrence (1.7%) was detected during a mean follow-up of 19.4 months (range 12 to 33), and in those with known renal cell carcinoma, none had evidence of distant progression (0%). The local recurrence was successfully re-ablated such that all 109 cases had no clinical or radiographic evidence of disease at last follow-up. Three patients died of causes unrelated to cancer. CONCLUSIONS: The results of our study have shown that in the short term, RFA appears to be a reasonable therapeutic nephron-sparing approach for treating select patients with small renal tumors. The cancer control appears adequate to date, but longer follow-up is necessary before widespread application.