Clinical-Radiomics Nomogram for Risk Prediction of Esophageal Fistula in Patients with Esophageal Squamous Cell Carcinoma Treated by IMRT or VMAT

Abstract Background and purpose: To analyze the predictive factors and establish a prediction model of esophageal fistula (EF) in patients with esophageal squamous cell carcinoma (ESCC) received intensity-modulated radiotherapy (IMRT) or Volumetric Modulated Arc Therapy (VMAT). Materials and Methods: Patients with ESCC treated with IMRT or VMAT from 2013 to 2020 in Xijing hospital were retrospectively analyzed. 43 patients with EF and 129 patients without EF were included in the analysis by 1:3 propensity score matching (time of diagnosis, gender). The clinical characters and radiomic features were recorded and extracted. Univariate and multivariate stepwise logistic regression analyses were provided to determine the risk factors associated with EF. Results: The median follow-up time was 23.96 months (range 1.3-104.9 m), and the median OS of EF patients was 13.1 months. 1158 radiomics features were extracted and 8 radiomics features were selected. The area under the receiver operating characteristic curve (AUC) value of radiomic signature calculated by selected features for predicting EF was 0.794. Multivariate analysis showed that the tumor length, tumor volume, T stage, lymphocyte rate and grade 4 esophagus stenosis were related to EF, and the AUC value of clinical nomogram for predicting EF was 0.849. The clinical-radiomics nomogram had the best performance in predicting EF with an AUC value of 0.896. Conclusions: The clinical-radiomics nomogram can predict the risk of EF in ESCC patients and be helpful for individualized treatment of esophageal cancer.