Development and validation of magnetic resonance imaging-based nomograms for patients with perihilar cholangiocarcinoma after radical resection: Preoperative prediction of survival

Abstract

BackgroundSurvival status prediction for perihilar cholangiocarcinoma (pCCA) patients is essential for postoperative clinical decision making. This study aimed to develop and validate prediction models for overall survival (OS) evaluation in pCCA patients preoperatively.Materials and MethodsA total of 184 patients who had curative resection for pCCA between January 2010 and December 2018 were enrolled. 110 patients were randomly selected for model development while other 74 patients for model testing. Imaging-derived radiomics signatures were developed. Independent preoperative clinical predictors were involved independently or in combination with radiomics signatures to construct different preoperative models through multivariable Cox proportional hazards method. The nomograms were constructed to predict OS, and the performance of which was evaluated by the discrimination ability, time-dependent receiver operating characteristic curve (ROC), calibration curve and decision curve.ResultsThe clinical model (Modelclinic) was constructed based on three independent variables including preoperative CEA, cN stage and invasion of hepatic artery in images. The model with best performance (Modelclinic&AP&PVP) was build based on three independent variables, SignatureAP and SignaturePVP. In training and testing cohorts, the concordance indexes (C-indexes) of Modelclinic were 0.846 (95% CI, 0.735-0.957) and 0.755 (95% CI, 0.540-969), and Modelclinic&AP&PVP manifested favorable performance with C-indexes of 0.962 (95% CI, 0.905-1) and 0.814 (95% CI, 0.569-1), and both of them outperformed TNM staging system (C-indexes, 0.616, 95% CI, 0.522-0.711 and 0.599, 95% CI, 0.490-0.708). Good agreement was observed in the calibration curves, and favorable clinical utility was validated using the decision curve analysis both for Modelclinic and Modelclinic&AP&PVP.ConclusionsTwo preoperative nomograms were constructed to predict 1-, 3- and 5-years survival following surgery for individual pCCA patients. Such methods are easy to be performed which have clinical application potential for decision-making and patients stratification in randomized, controlled trials.