Percutaneous ablation versus robotic partial nephrectomy in the treatment of cT1b renal tumors. Oncologic and functional outcomes of a propensity score-weighted analysis

Abstract Introduction To assess oncologic and functional outcomes of both percutaneous ablation (cryoablation [CA] and radiofrequency ablation [RFA]) and Robot-assisted Partial Nephrectomy (RAPN) in the treatment of renal tumors larger than 4 cm. Materials & Methods We retrospectively analyzed prospectively collected data from 102 consecutive patients, who underwent minimally invasive treatment for cT1b renal tumors at our institution. Primary renal function outcome was assessed by estimated Glomerular Filtration Rate (eGFR) preservation at baseline and 1 year postoperatively. Peri-operative data, functional and oncological outcome were collected. Multivariate regression models were used to compare functional outcomes between groups. Cancer-specific survival (CSS) and recurrence-free survival (RFS) were estimated at two years using the Kaplan-Meier method and compared with Cox proportional hazards regression model to calculate hazard ratios (HR). To control for selection bias between the different treatments, we adjusted our models with an Inverse Probability of Treatment Weighting (IPTW) propensity score. Results There was no significant difference in renal preservation between the groups (p = 0.664). Multivariate analysis did not show a statistically significant difference in terms of renal function outcomes between RAPN and PTA groups. The adjusted hazard ratio regarding the local recurrence-free survival was significantly shorter for the CA group (HR 4.3, IC95%, 1.78-10.37); p=0.001). Conclusions Our study demonstrated the equivalence between RAPN and percutaneous ablative techniques for the preservation of renal function in the treatment of T1b tumors. RAPN offers a better local control than percutaneous ablation, in terms of primary success rate.