Background and purpose: Needle ablative therapies are being offered to patients presenting with small renal masses, but long-term outcomes are currently unavailable. We report our intermediate-term results (1-4 years) after radiofrequency ablation (RFA) of small (<4-cm) renal masses.
Patients and methods: At our institution, all renal tumors treated using RFA since May 2001 have been recorded in a prospective database. During this time, 94 tumors (mean size 2.4 cm; range 1-4.2 cm) in 78 patients were treated using a temperature-based RFA generator by either a percutaneous (59%) or a laparoscopic approach. The patients followed with imaging at 6 weeks, 3 and 6 months, and every 6 months thereafter. Only patients with at least 12 months of follow-up were eligible for this analysis; the mean follow-up was 25 months.
Results: Of the 89% of masses that were biopsied, 77% were renal-cell carcinomas (RCC), of which 66% were Fuhrman grade 1, 31% were grade 2, and 3% were grade 3. Three recurrences were noted, for an overall recurrence-free rate of 96.8%. In this patient population with numerous comorbid conditions, there were six deaths but only one related to renal cancer, for a cancer-specific survival rate of 98.5% and an overall survival rate of 92.3%.
Conclusion: In the intermediate term (1-4 years), the oncologic effectiveness of RFA appears comparable to that of traditional treatments offered for small renal masses. Further studies of larger numbers of patients with longer follow-up are needed.