Should Patients with Renal Cell Carcinoma and Pathological Nodal Invasion Be Classified As Having Stage IV Disease?

Background: Lymph node invasion is associated with poor outcome in patients with renal cell carcinoma (RCC). Patients and Methods: Patients with RCC within a single center from 2001 to 2018 were retrospectively obtained from the Chang Gung Research Database. Patient gender, physical status, Charlson Comorbidity Index, tumor side, histology, age at diagnosis, and body mass index (BMI) were compared. The overall survival (OS) and cancer-specific survival (CSS) of each group were estimated using the Kaplan–Meier method. Log-rank tests were used to compare between the subgroups. Results and Conclusions: A total of 335 patients were enrolled, of whom 76 had pT₃N₀M₀, 29 had pT_1–3N₁M₀, 104 had T_1–4N₀M₁, and 126 had T_1–4N₁M₁ disease. Significant OS difference was noted between pT₃N₀M₀ and pT_1–3N₁M₀ groups with 12.08 years [95% confidence interval (CI), 8.33–15.84] versus 2.58 years (95% CI, 1.32–3.85), respectively (P < 0.005). No significant difference was observed in OS between pT_1–3N₁M₀ and T_1–4N₀M₁ groups with 2.58 years (95% CI, 1.32–3.85) versus 2.50 years (95% CI, 1.85–3.15, P = 0.72). The OS of N₁M₁ group was worse than that of N₀M₁ group with 1.00 year (95% CI, 0.74–1.26) versus 2.50 years (95% CI, 1.85–3.15, P < 0.05). Similar results were also observed in CSS. In summary, we claim that RCC with lymph node (LN) invasion should be reclassified as stage IV disease in terms of survival outcome.