Prognostic value of the preoperative C-reactive protein-to-lymphocyte ratio in patients with non-metastatic clear cell renal cell carcinoma

BACKGROUND: Systemic inflammation is associated with the prognosis of clear cell renal cell carcinoma (ccRCC). The C-reactive protein-to-lymphocyte ratio (CLR) combines systemic inflammation and host immune status. However, its prognostic value in non-metastatic ccRCC remains unclear. This study evaluated the association between preoperative CLR and survival outcomes in patients with non-metastatic ccRCC. METHODS: We retrospectively included 414 patients with non-metastatic ccRCC who underwent partial or radical nephrectomy. The primary Cox analyses treated ln(CLR) as a continuous variable and assessed overall survival (OS) and the cause-specific hazard of ccRCC-related death. Sensitivity analyses included expanded adjustment and time-varying effects. Cut-off-based analyses were exploratory. Time-dependent receiver operating characteristic curves were used to compare CLR with other inflammatory markers. Incremental discrimination and calibration were assessed using bootstrap internal validation. RESULTS: After adjustment for age, Fuhrman grade, and T stage, ln(CLR) remained independently associated with OS (HR = 1.589, 95% CI 1.257-2.009; P < 0.001) and ccRCC-related death (HR = 1.612, 95% CI 1.266-2.052; P < 0.001). The associations persisted in sensitivity analyses addressing additional pathological factors and time-varying effects. The 3- and 5-year AUCs of CLR for OS were 0.810 and 0.776, respectively. No statistically significant AUC differences were detected between CLR and CRP, NLR, or CAR. Adding CLR increased the apparent C-index from 0.843 to 0.885. After bootstrap optimism correction, the C-indices were 0.832 and 0.873, respectively (ΔC-index = 0.041). Calibration was assessed at 3 and 5 years. CONCLUSIONS: Preoperative CLR was independently associated with OS and the cause-specific hazard of ccRCC-related death in this single-center cohort. Adding CLR improved discrimination after internal validation, but its superiority over other inflammatory markers and clinical utility remain unestablished. Independent multicenter validation is needed.