High incidence of tracheobronchial diverticulum in esophageal cancer patients: a retrospective survey alerting pitfall during thoracoscopic esophagectomy

Objectives Although tracheobronchial diverticulum (DV) rarely cause problems, attention should be paid during esophagectomy, which requires careful dissection around the trachea and bronchi. Here, we retrospectively review cases of tracheobronchial DVs among esophageal cancer patients and report two cases of bronchial DV injury during thoracoscopic esophagectomy that were successfully repaired. Methods The thin-section CT images of esophageal cancer patients who underwent thoracoscopic esophagectomy from January 2013 to December 2015 were retrospectively reviewed. The localization, number, and size (largest axial diameter) of all detected DVs were recorded. Results A total of 180 patients were enrolled in this study. The incidence of tracheal DV was 5.0%, and that of bronchial DV was 40.0%. The median diameter of the tracheal diverticula was 2.45 [interquartile range (IQR) 2.00-8.17] mm and that of the bronchial diverticula was 1.90 (IQR 1.51-2.46) mm. All tracheal diverticula presented at the right tracheal wall 4.5-6.0 cm below the vocal cords; bronchial diverticula presented at the subcarinal lesions. We experienced two cases with bronchial diverticulum injuries during thoracoscopic esophagectomy, which were repaired by primary closure and confirmed that there was no air leak. No postoperative complications associated with bronchial injury occurred in either patient. Conclusion Since tracheobronchial DVs are not as rare as previously thought, careful evaluation of thin-slice CT scans is necessary before thoracoscopic esophagectomy. If a tracheobronchial DV is injured during surgery, it is important to carefully repair it and confirm that there is no air leak to avoid complications.