A Retrospective Study of a Postoperative Inflammation-Based Score for Predicting Disease-Free Survival in Locally Advanced Rectal Cancer After Neoadjuvant Chemoradiotherapy

Background: Growing research findings highlight the potential of inflammatory markers measured after surgery as prognostic indicators for survival outcomes in rectal carcinoma patients. However, their precise clinical significance remains inadequately explored within the specific population of locally advanced rectal carcinoma (LARC) patients receiving neoadjuvant chemoradiotherapy (NCRT), particularly regarding therapeutic response evaluation and long-term disease progression patterns. Methods: This investigation enrolled 260 participants diagnosed with LARC who underwent NCRT from 2014 to 2024. The study measured postoperative neutrophil-lymphocyte ratio (NLR) and monocyte-lymphocyte ratio (MLR) through ROC curve analysis to evaluate systemic inflammation. Participants were categorized into three cohorts based on inflammation-based postoperative biomarker score (IPBS): Score 0 (postoperative NLR 0.345), and Score 1 encompassing cases not meeting these thresholds. Survival outcomes were analyzed using Kaplan-Meier methodology stratified by inflammatory marker levels and IPBS classifications. Multivariate Cox regression models were employed to identify prognostic factors influencing OS and DFS. Results: Initial univariate assessments revealed significant correlations between disease-free survival and several factors including ypTNM staging, histopathological evidence of vascular/lymphatic/perineural invasion, postoperative neutrophil-lymphocyte ratio, and the IPBS system. Subsequent multivariate modeling identified elevated ypTNM classification (HR=2.115, 95% CI:1.114-4.019, p=0.022) and increased IPBS (HR=1.798, 95% CI:1.049-3.083, p=0.033) as independent prognostic indicators for reduced DFS. Notably, postoperative NLR values failed to demonstrate statistical significance in multivariate evaluation (HR=1.588, 95% CI:0.910-2.772, p=0.104). Conclusion: The composite inflammation-based postoperative biomarker score model demonstrated superior predictive accuracy for DFS outcomes in LARC patients undergoing NCRT compared to isolated biomarker analysis or select histopathological characteristics.