Survival Analysis And Predictive Modelbased On TNM Stage Of Patients With Thymic Epithelial Tumors After Extended Thymectomy

Aim:The aim of this study were to investigate the independent risk factors for prognosis of patients with thymic epithelial tumors(TETs)after extended thymectomy and to establish a survival prediction model based on TNM staging to provide a theoretical basis for patient survival prediction and postoperative individualized treatment decision.Methods:Patients with TETs who underwent extended thymectomy between January 2010 and December 2020 were consecutively enrolled.An analysis of multivariate Cox regression and stepwise regression using the Akaike information criterion(AIC)was conducted to identify prognostic factors,and a nomogram for TETs was derived from the results of these analyses.The model was validated internally with the Kaplan-Meier curves,tdROC curves and calibration curves.Results:There were 350 patients with TETs enrolled in the study,and they were divided into a training group(245,0.7)and a validation group(105,0.3).Age(HR=7.47,95%CI 2.05-27.30,P=0.002),histological type B3/CA(HR=14.40,95%CI 1.18-175.00,P=0.004),maximum tumor diameter(HR=6.36.95%CI 1.61-25.10,P=0.008),myasthenia gravis(HR=3.77,95%CI 1.08-13.20,P=0.038),and TNM stage Ⅱ(HR=14.10,95%CI 2.80-71.50,P=0.001),Ⅲ/Ⅳ(HR=43.70,95%CI 6.19-308.00,P<0.001)were independent prognostic factors for cancer-specific survival(CSS).A nomogram for CSS was formulated based on the independent prognostic factors and exhibited good discriminative ability as a means of predicting CSS,as evidenced by the area under the ROC curves(AUCs)of 3-year,5-year,and 10-year being 0.946,0.949,and 0.937,respectively.The Kaplan-Meier curves showed a significant difference between high nomoRisk group and low nomoRisk group.The calibration curves further revealed excellent consistency between the predicted and actual mortality when using this nomogram.Conclusion:There are several prognostic factors for TETs.Based on TNM stage and other prognostic factors,the nomogram accurately predicted the 3-,5-,and 10-year mortality rates of patients with TETs in this study.The nomogram could be used to stratify risk and optimize therapy for individual patients.