Abstract
OBJECTIVE: To evaluate the long-term oncological outcomes of partial nephrectomy (PN) in patients with renal cell carcinoma (RCC) who were clinically staged as clinical T1 (cT1) preoperatively but upstaged to pathological T3a (pT3a) after surgery. METHODS: A total of 427 RCC patients postoperatively diagnosed as pT3aN0M0 at Peking University Third Hospital from February 2013 to December 2022 were retrospectively reviewed. Among them, 33 cT1 patients upstaged to pT3a RCC received PN (PN group), while 394 non-upstaged pT3a RCC patients underwent radical nephrectomy (RN, RN group). Propensity score matching was performed at a 1 ∶ 1 ratio based on baseline characteristics. The Kaplan-Meier method was used to assess overall survival (OS), cancer-specific survival (CSS), and disease-free survival (DFS), with Log-rank tests and Cox regression models for multivariate analysis. RESULTS: Before matching, the PN group (n = 33) had significantly higher rates of perirenal fat invasion (PFI, 45.5% vs. 15.2%) and segmental renal vein involvement (42.4% vs. 20.8%), but lower rates of renal sinus invasion (RSI, 21.2% vs. 73.6%) and renal vein tumor thrombus (0% vs. 15.2%) compared with the RN group (n = 394, all P < 0.05). After matching, baseline characteristics were comparable between the PN group (n = 33) and RN group (n = 33). No significant differences were observed in operative time, blood loss, mean hospital stay, complication rate, positive margin rate, or conversion to open surgery between the two groups (P > 0.05). However, the PN group showed significantly higher estimated glomerular filtration rate (eGFR) postoperatively [76.9 (55.4, 87.3) mL/(min·1.73 m(2)) vs. 61.7 (56.8, 73.5) mL/(min·1.73 m(2)), P < 0.05], indicating better renal function preservation. No significant differences were found in OS, CSS, or DFS between the groups (P > 0.05). Multivariate ana-lysis identified renal vein invasion (RVI), higher Fuhrman grades (Ⅲ-Ⅳ), and sarcomatoid differentiation as independent risk factors for DFS and CSS in the pT3a RCC patients (P < 0.05). CONCLUSION: For cT1 RCC patients upstaged to pT3a, PN preserves renal function more effectively while achieving com-parable oncological outcomes to RN. RVI, higher Fuhrmann grade, and sarcomatoid differentiation are independent risk factors for pT3N0M0 RCC patients.