Abstract: Objective The aim of this study was to develop a predictive model for early recurrence and distant metastasis in patients with early-onset colorectal cancer (EOCRC) following surgery,and to validate its predictive value.Methods A retrospective analysis was conducted on the clinical data of 256 patients with EOCRC who underwent surgery at the 900th Hospital of PLA Joint Logistics Support Force from December 2014 to December 2020,with a follow-up period of three years post-surgery.Patients were divided into a recurrence and metastasis group (n=121) and a non-recurrence and metastasis group (n=135) based on the occurrence of recurrence and distant metastasis after surgery.Preoperative peripheral blood indicators and postoperative pathological characteristics were analyzed and compared between the two groups.Univariate and multivariate Logistic regression analyses were performed using R software (version 4.4.3) to identify potential risk factors.A nomogram prediction model was constructed based on the results of multivariate analysis.Receiver Operating Characteristic (ROC) curves,calibration curves,and Decision Curve Analysis (DCA) curves were plotted to evaluate and validate the predictive performance of the model.Results Of the 256 patients,121 experienced early recurrence and distant metastasis post-surgery,with a recurrence and metastasis rate of 47.3%.Multivariate Logistic regression analysis revealed that T stage,N stage,vascular/neural invasion,other histological types (mucinous adenocarcinoma/signet ring cell carcinoma),CEA,HRR,TyG,and PNI were independent risk factors for early recurrence and distant metastasis after EOCRC surgery.The area under the ROC curve of the model was 0.858(95%CI0.812~0.904).Based on the area under the ROC curve,calibration curves,and DCA curves,the model demonstrated good predictive performance.The web-based dynamic nomogram is accessible via this link:https://eocrc.shinyapps.io/dynnomapp/.Conclusion The nomogram can accurately predict the risk of early recurrence and distant metastasis within three years after EOCRC surgery,providing individualized clinical decision-making for future clinical diagnosis and treatment of EOCRC.

Key words: early-onset colorectal cancer, early recurrence , early distant metastasis, nomogram model, Logistic regression analysis, web-based dynamic nomogram