Analysis Of Risk Factors For Lymph Node Metastasis In Patients With Stage Ⅰ-Ⅲ Colorectal Cancer And Construction Of Nomogram Prediction Model

Objective: To investigate the risk factors associated with lymph node metastasis in patients with stage Ⅰ-Ⅲ colorectal cancer,and to construct and validate a nomogram prediction model.Methods: A retrospective study was conducted to collect the clinicopathological data of patients with stage Ⅰ-Ⅲ colorectal cancer who got radical resection in the Department of Gastrointestinal Surgery,the First Affiliated Hospital of Xinjiang Medical University from January 2019 to December 2021.According to the postoperative pathological results,patients were divided into two groups: lymph node metastasis group and non-metastasis group.Multivariate Logistic regression was used to analyze the influencing factors of colorectal cancer lymph node metastasis after R language software variables were screened,and the nomogram prediction model was established.The area under the ROC curve(AUC),correction curve and decision curve were used to analyze,and the model discrimination was verified by C-index.The accuracy of probability prediction was evaluated by Brier score to comprehensively evaluate the discrimination,accuracy and clinical practicality of the prediction model.Results: A total of 348 patients were included in this study,and 121(34.8%)patients with lymph node metastasis were confirmed by postoperative pathology.There were significant differences in carcinoembryonic antigen level,tumor differentiation degree,pathological type,T stage,nerve and vascular invasion,and cancer nodules between lymph node metastasis group and non-metastasis group(all P<0.05).The results of multivariate Logistic regression showed that vascular invasion(OR=3.823,95%CI:1.952-7.678),cancer nodules(OR=7.120,95%CI:2.561-23.254),T stage(OR=2.547,95%CI:1.418-4.716)was an independent risk factor for lymph node metastasis in patients with stage Ⅰ-Ⅲ colorectal cancer(all P<0.05).The nomogram model showed that the area under the curve AUC of this graph in predicting the risk of lymph node metastasis in patients with stage Ⅰ-Ⅲcolorectal cancer was 0.766(95%CI:0.714-0.818),the sensitivity and specificity were62.8% and 80.2%,and the Brier score was 0.180.Internal validation C index of calibration curve was 0.720,Brier score was 0.200;The results of decision curve evaluation show that the model has certain clinical practicability.Conclusions: Vascular invasion,tumor nodule and T stage are independent risk factors for lymph node metastasis in patients with stageⅠ-Ⅲ colorectal cancer.The nomogram prediction model based on multivariate Logistic regression has a good predictive value for lymph node metastasis,and the internal verification results are satisfactory,which can provide a certain reference for clinical diagnosis and treatment.