A nomogram to predict stricture after endoscopic submucosal dissection for early esophageal cancer

Background: Risk factors of esophageal stricture after ESD are inconsistent and incomprehensive, the present study aimed to identify a robust model to predict postoperative stricture. Methods: : This retrospective study included 273 individuals underwent ESD for early esophageal cancer from January 1, 2014 to October 30, 2020 in Beijing Friendship Hospital. Univariate Cox proportional hazard regression was used to estimate potential factors of stricture after ESD, followed by multivariate Cox proportional hazard regression to identify significant independent predictors after adjusting for covariates. Nomogram building based on multivariate Cox regression model was used to evaluate accuracy and discrimination by ROC curves and calibration curves respectively. Results: : Stricture was identified in 28 patients (10%). The other patients were enrolled in non-stricture group (n=243). Multivariate Cox proportional hazard model demonstrated that operation time (HR 1.01, 95%CI: 1.00-1.01, P <0.01), upper segment of esophagus (HR 6.48, 95%CI: 2.07-20.33, P <0.01), middle segment of esophagus (HR 3.42, 95%CI: 1.36-8.64, P 3/4 circumferential lumen of esophagus (HR 6.32, 95%CI: 2.20-18.13, P <0.01), postoperative fever (HR 6.17, 95%CI: 1.75-21.77, P <0.01), were independent predictive factors for postoperative stricture. The predictive accuracy of the nomogram was estimated by the AUC of ROC curves was 0.93, 0.87, 0.87 at 1 year, 2 years, and 3 years respectively. Conclusion: Longer operation time, >3/4 of the circumferential lumen of esophagus, located at upper and middle esophageal segment, and postoperative fever were independent risk factors of esophageal stricture after ESD.