Overall survival and oncological outcomes after partial nephrectomy and radical nephrectomy for cT2a renal tumors: A collaborative international study from the French kidney cancer research network UroCCR.

BACKGROUND: Partial nephrectomy (PN) is recommended as first-line treatment for cT1 stage kidney tumors because of a better renal function and probably a better overall survival than radical nephrectomy (RN). For larger tumors, PN has a controversial position due to lack of evidence showing good cancer control. The aim of this study was to compare the results of PN and RN in cT2a stage on overall survival and oncological results. METHOD: A retrospective international multicenter study was conducted in the frame of the French kidney cancer research network (UroCCR). We considered all patients aged≥18 years who underwent surgical treatment for localized renal cell carcinoma (RCC) stage cT2a (7.1-10cm) between 2000 and 2014. Cox and Fine-Gray models were performed to analyze overall survival (OS), cancer specific survival (CSS) and cancer-free survival (CFS). Comparison between PN and RN was realized after an adjustment by propensity score considering predefined confounding factors: age, sex, tumor size, pT stage of the TNM classification, histological type, ISUP grade, ASA score. RESULTS: A total of 267 patients were included. OS at 3 and 5 years was 93.6% and 78.7% after PN and 88.0% and 76.2% after RN, respectively. CSS at 3 and 5 years was 95.4% and 80.2% after PN and 91.0% and 85.0% after RN. No significant difference between groups was found after propensity score adjustment for OS (HR 0.87, 95% CI: 0.37-2.05, P=0.75), CSS (HR 0.52, 95% CI: 0.18-1.54, P=0.24) and CFS (HR 1.02, 95% CI: 0.50-2.09, P=0.96). CONCLUSION: PN seems equivalent to RN for OS, CSS and CFS in cT2a stage kidney tumors. The risk of recurrence is probably more related to prognostic factors than the surgical technique. The decision to perform a PN should depend on technical feasibility rather than tumor size, both to imperative and elective situation. LEVEL OF EVIDENCE: 4.