Abstract
BACKGROUND: This study investigated the prognostic role of tumor necrosis (TN) in non-metastatic clear cell renal cell carcinoma (ccRCC). METHODS: We enrolled 1,212 non-metastatic ccRCC patients undergoing nephrectomy (2013-2023) in this retrospective study. Computer-generated randomization allocated cases to derivation (70%, n = 848) and validation cohorts (30%, n = 364). Kaplan-Meier methodology compared overall survival (OS), cancer-specific survival (CSS), and recurrence-free survival (RFS) across TN-positive and TN-negative cohorts, with intergroup differences evaluated by log-rank testing. Prognostic determinants were identified through univariate and multivariate Cox proportional hazards regression. We developed a prognostic nomogram through stepwise Cox regression that integrated TN status with key clinicopathological variables. Validation employed: Harrell's C-index, time-dependent ROC curves, calibration plots, and decision curve analysis (DCA). RESULTS: TN positivity was significantly associated with reduced OS (HR: 2.12, 95% CI: 1.65-2.73; P < 0.001), CSS (HR: 2.45, 95% CI: 1.82-3.29; P < 0.001), and RFS (HR: 1.89, 95% CI: 1.32-2.70; P = 0.003) in multivariate analysis. The prognostic nomogram demonstrated excellent discrimination in the validation cohort, with C-indices of 0.855 (OS), 0.870 (CSS), and 0.724 (RFS). Time-dependent ROC analysis revealed robust predictive accuracy for OS at 1- (AUC: 0.892), 3- (AUC: 0.846), and 5-year (AUC: 0.826) intervals. Calibration curves demonstrated excellent consistency between predicted probabilities and actual outcomes. Decision curve analysis further revealed greater clinical net benefit than pT stage system and WHO/ISUP classification. CONCLUSION: TN is an independent prognostic marker in non-metastatic ccRCC. The novel nomogram integrating TN provides reliable risk stratification, aiding personalized postoperative management.