Abstract
PURPOSE: To evaluate oncological and functional outcomes of minimally invasive partial and radical nephrectomy (MIS-PN vs. MIS-RN) in patients with pT3aN0M0 renal cell carcinoma (RCC). MATERIALS AND METHODS: We performed a multicenter retrospective study of patients with pT3aN0M0 RCC treated with MIS-PN or MIS-RN. The primary outcome was recurrence-free survival (RFS). Secondary outcomes included de novo eGFR <60 mL/min/ 1.73 m2 (CKD-S) and <45 mL/min/ 1.73 m2 (CKD-S3b) at the new baseline (1-12 month postoperatively), as well as CKD-S at the latest follow-up (>1 year postoperatively). A 1:2 ratio propensity score matching (PSM) was applied to balance covariates, and inverse probability weighting (IPW) served as sensitivity analysis. Survival curves were estimated using the Kaplan-Meier method, and multivariable analyses (MVA) were performed to identify predictors of oncological and functional outcomes. RESULTS: A total of 303 patients were enrolled (113 MIS-PN/190 MIS-RN) with a median follow-up of 39.0 months (IQR 26.8-52.9). After PSM (66 MIS-PN/54 MIS-RN), no significant difference in RFS was observed between two groups (p=0.23). MVA revealed that surgical approach was not an independent predictor of RFS (HR: 1.00, p=1.00). Among patients with available new baseline eGFR after PSM (41 MIS-PN/37 MIS-RN), MIS-RN was independently associated with a higher risk of CKD-S (OR: 7.96, p=0.03). Among patients with available the latest follow-up eGFR after PSM (41 MIS-PN/37 MIS-RN), MIS-RN remained an independent predictor of CKD-S at the latest follow-up (OR: 7.98, p=0.03). IPW analysis yielded consistent results. Additionally, IPW identified MIS-RN as an independent risk factor for CKD-S3b at the new baseline (OR: 18.29, p<0.01). CONCLUSION: MIS-PN provided comparable mild term oncologic outcomes to MIS-RN while offering superior renal function preservation. MIS-PN may be a viable option for selected T3a RCC patients when nephron preservation is indicated.