Partial nephrectomy Vs. Percutaneous thermal ablation of small renal masses

Background: Percutaneous thermal ablation (TA), partial nephrectomy (PN), and active surveillance with delayed intervention in tumors smaller than 3 cm are the recommended treatments for small renal masses (SRMs). In this study, we investigated the post-operative course and the long-term oncological results of TA and PN, to identify the best candidates for each technology. Methodology: Patients with SRMs underwent either TA (77 patients) or PN (100 patients), according to surgeon and patient preferences. TA patients were significantly older (67.4 years ±0.2 vs. 60.0 years ±12, p < 0.01), sicker (Charlson comorbidity index of 0.85±36 vs. 0.39±0.94, p < 0.01), and their tumors were smaller by an average of 3 mm. Results: TA was associated with significantly shorter hospital stay (1.9 days ±0.4 vs. 5.5 days ±3.2, p < 0.01), smaller burden of treatment score (13.4 ± 6.7 vs. 26.9 ± 7.5, p < 0.01) and fewer complications. The 5-year recurrence-free survival rates after a single TA intervention and after PN were 83.5 % and 98.1 %, respectively (p < 0.01). The 5-year recurrence-free survival rate after TA was dependent on tumor diameter (100 % in tumors < 2.4 cm and 58.4 % in tumors 2.4–4 cm, p < 0.01) and independent of tumor diameter after PN. Conclusions: TA is an effective treatment for kidney tumors smaller than 2.4 cm. Compared to PN, it provides the benefits of shorter hospitalization, lower burden of treatment, fewer complications, and excellent recurrence-free status after a single intervention. This finding suggests that 2.4 cm and not 3 cm may be the preferred cutoff for converting from active surveillance to active treatment. PN is the preferred treatment for patients with tumors>2.4 cm.