Purpose: To compare the outcomes of percutaneous ablation (PA) versus nephrectomy (NE) for small renal masses (SRMs) in patients with T1 renal cell carcinoma and evaluate the role of pre-procedural biopsy in the treatment of SRM.
Materials and methods: Retrospective cohort analysis of patients subjected to PA or NE for SRM (< 5 cm) from January 2006 to August 2016. A total of 231 patients with T1 SRM were included in the main analysis. Patient demographics, tumor characteristics, biopsy and procedural details, clinical outcomes, complication rates, and changes in renal function were compared in patients with malignant SRMs. Survival rates were compared using log-rank test.
Results: A total of 142 patients underwent PA and 89 patients underwent NE, with a respective mean follow-up period of 2.50 (SD 1.77) and 1.85 (SD 0.97) years (P = 0.029). Rate of intervention for benign tumors was similar in PA (n = 21, 15%) and NE (n = 16, 18%; P = 0.520) without routine pre-procedural biopsy. Routine pre-procedural biopsy resulted in zero benign tumors treated in the PA cohort. Tumor recurrence was similar and cumulative survival was similar in both groups (P = 0.287). Residual tumor was observed in 18 PA patients. Complication rates were lower for PA than for NE (9 vs 30%, P < 0.001). A significant reduction in eGFR was observed after NE (12.1 mL/min/1.73 m2; P = 0.009) relative to PA (5.9 mL/min/1.73 m2; P = 0.060).
Conclusion: PA is a safe alternative to NE in the treatment of SRM, with similar overall survival and decreased complication rates. Pre-procedural biopsy decreases the rate of intervention for benign tumors and should be routinely performed.
Keywords: Nephrectomy; Percutaneous ablation; Radiofrequency ablation; Renal cell carcinoma; Small renal mass.