Prognostic Nomogram To Predict The Overall Survival Of Patients With Early-onset Colorectal Cancer:a Population-based Analysis

Background:Compared to the decreasing incidence of colorectal cancer in older populations,the incidence of early-onset colorectal cancer(EO-CRC,aged <50 years)increased by approximately 2% annually since the mid-1990 s.It is necessary to find prognostic factors and predict the prognosis of EO-CRC patients.The present study aimed to determine clinicopathological and socio-economic prognostic factors associated with the overall survival of EO-CRC patients,then to establish and validate a prognostic nomogram for patients with EO-CRC.Methods:Eligible patients with early-onset colorectal cancer diagnosed from 2010 to 2017 were extracted from the Surveillance,Epidemiology,and End Results(SEER)database.Patients were randomly divided into a training cohort and a test cohort.Independent prognostic factors were obtained from the training cohort using univariate and multivariate Cox analyses and were used to establish a nomogram for predicting 3-and5-year overall survival(OS).The discriminative ability and calibration of the nomogram were assessed using C-index values,ROC curves,and calibration plots.The test cohort data are used to perform internal validation.Finally,the prediction ability of the nomogram was compared with that of the AJCC TNM staging system.Results:A total of 5585 patients with EO-CRC were included in the study.Based on the univariate and multivariate Cox analyses,15 independent prognostic factors were assembled into the nomogram to predict 3-,and 5-year OS.The nomogram showed favorable discriminatory ability as indicated by the C-index(0.840,95% CI0.827–0.850),and the 3-,and 5-year AUC values(0.868 and 0.84869,respectively).Calibration plots indicated optimal agreement between the nomogram-predicted survival and the actual observed survival.The results remained reproducible in the test cohort.The nomogram had a higher C-index(0.840 vs 0.804,P<0.001),higher likelihood,and lower AIC than the AJCC TNM staging system.Conclusion:After adjusting for other factors,race,primary site,histology,grade,tumor size,regional nodes examined,LNR,liver metastasis,lung metastasis,bone metastasis,TNM stage,T stage,CEA,perineural invasion,median household income were independent prognostic factors of EO-CRC patients.A novel nomogram for EO-CRC patients based on independent clinicopathological and socio-economic factors was developed,which performs better than the AJCC TNM staging system.The nomogram could facilitate individual prognosis prediction and clinical decision-making.