Node Positive Resected Renal Cell Carcinoma Portends a Poor Prognosis: Results From the Canadian Kidney Cancer Collaboration

INTRODUCTION: To characterize recurrence and survival patterns in pathologically node-positive, nonmetastatic (pN1M0) renal cell carcinoma (RCC) and identify prognostic factors. PATIENTS AND METHODS: Patients with pTanyN1M0 clear cell, papillary, or chromophobe RCC from the Canadian Kidney Cancer Information System who underwent radical or partial nephrectomy with lymph node dissection between 2011 and 2023 were included. Recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS) were estimated using Kaplan-Meier methods. Prognostic factors were assessed using univariable and multivariable Cox proportional hazards models. RESULTS: One hundred thirteen patients (69% male) were followed for a median of 3.1 years (IQR 1.2-6.0). Recurrence occurred in 77% (n = 87/113) at a median of 4.8 months (IQR 3.6-7.2), predominantly with distant metastases (n = 59/87). Median CSS was 5.5 years (IQR 3.8-nonestimable) and median OS was 4.4 years (IQR 3.4-6.5). On univariable analysis, pT3/T4 stage (HR 2.14, 95% CI 1.43-3.19, P < .001) and necrosis (HR 0.70, 95% CI 0.54-0.90, P = .006) were associated with RFS. Sarcomatoid differentiation was associated with CSS (HR 2.55, P = .025) and OS (HR 2.73, P = .013). On multivariable analysis, necrosis (adjusted HR 0.61, 95% CI 0.47-0.79, P < .001) and sarcomatoid differentiation (adjusted HR 2.69, 95% CI 1.01-7.21, P = .049) remained independently associated with RFS and CSS, respectively. CONCLUSION: Patients with pN1M0 RCC experience rapid, frequent recurrences predominantly with metastatic disease, with survival outcomes resembling metastatic RCC. Restaging imaging prior to adjuvant immunotherapy initiation is essential to identify patients who may have already progressed.