Development and validation of a web-based nomogram for predicting cancer-specific survival in patients with intrahepatic cholangiocarcinoma: A SEER database analysis

Abstract

Background Intrahepatic cholangiocarcinoma (ICCA) is one of the most malignant tumors of the biliary system. This study aims to develop and validate a prognostic nomogram that can estimate the probability of 1-, 3- and 5-year cancer-specific survival (CSS) for ICCA patients. Methods Clinical data of 1387 patients diagnosed with ICCA between 2010 and 2017 from the Surveillance, Epidemiology, and End Results database were analyzed. 970 patients were set as the training cohort to construct the nomogram while the rest 417 patients were set as the validation cohort. To compare the efficacy to predict 1-, 3-, and 5-year CSS of the nomogram with the 8th edition of the American Joint Committee on Cancer (AJCC) staging system, we evaluated the Harrell’s index of concordance (C-index), area under the receiver operating characteristic curve (AUC) and decision curve analysis (DCA) in both cohorts. Meanwhile, a dynamic network-based nomogram was published. Results Age, sex, AJCC T stage, AJCC N stage, AJCC M stage, surgery status, and tumor grade were selected as independent prognostic risk factors to build the nomogram. The C-index in the training and validation cohorts were 0.726 and 0.711 respectively. The AUCs in the training cohort for 1-, 3-, and 5-year CSS prediction were 0.787, 0.828, and 0.843. In the validation cohort, the AUCs were 0.776, 0.817, and 0.782. All of the AUCs of the nomogram for 1-, 3-, and 5-year CSS prediction performed better than the AJCC staging system. Moreover, the DCA analysis demonstrated the net benefit of the nomogram was better. The survival analysis showed the survival rate of patients classified as high-risk based on the nomogram score was significantly lower compared to those categorized as low-risk (p < 0.0001). Conclusions An accurate and convenient nomogram was established to assist clinicians in making more personalized prognosis predictions for ICCA patients.