Multiparametric Radiomics Nomogram May Be Used for Predicting the Severity of Esophageal Varices in Cirrhotic Patients

Abstract

Background: To explore whether the multiparametric radiomics nomogram on computed tomography (CT) images based on radiomics and relevant indices of esophageal varices(EV) can be used for predicting the EV severity in patients with cirrhotic livers. Methods: 136 consecutive patients with clinicopathologically confirmed liver cirrhosis from January 2016 to August 2018 were included for the predictive model development, patients were divided into non-conspicuous EV group(mild-to-moderate EV,n=30) and conspicuous EV group (severe EV,n=106) according to standard endoscopy validation. The radiomic scores(Rad-scores) were constructed from radiomics features of regions of interest(ROIs) in left liver(LL) and right liver(RL) respectively. The multiparametric nomogram was combined the better performance Rad-score and EV-relevant indices, the calibration, discrimination and clinical usefulness of developed nomogram were evaluated using calibration curves, decision curve analysis(DCA) and net reclassification index(NRI) analysis respectively. Findings: The LL Rad-score calculated from radiomics features was selected with relatively higher area under the curve(AUC; 0.88,training cohort; 0.865,validation cohort). In addition, cross-sectional surface area(CSA) was identified as the important predictor(P<0.05). The multiparametric nomogram containing LL Rad-score and CSA showed better predictive performance and good calibration in training(C-index,0.953[95%CI,0.892 to 0.973]) and validation cohort(C-index,0.938[95%CI, 0.841 to 0.961]), resulting in an improved NRI(categorical NRI of 25.9%(P=0.0128), continuous NRI of 120%(P=0)) and integrated discriminatory improvement (IDI=13.9%,P=0.00013). DCA demonstrated that the multiparametric radiomics nomogram was clinically useful. Interpretation: Multiparametric radiomics nomogram, which incorporates the liver radiomics signature and EV-relevant indices, is a useful tool for noninvasively predicting EV severity and may complement the standard endoscopy for evaluating EV severity in patients with cirrhosis. Funding Statement: The authors state: Not applicable. Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: This study had approval from the Institutional Review Board of West China Hospital, and informed consent requirement was waved.