Supplementary Material for: Evaluation of the Associations between Gastric Tube Preparation Methods and the Incidence of Cervical Anastomotic Leakage after Esophagectomy for Thoracic Esophageal Cancer

<b><i>Background:</i></b> A gastric tube (GT) is most often selected as a reconstruction conduit in esophageal reconstruction. Although some leakage from esophagogastric anastomoses is induced by blood flow failure in reconstruction conduits, the association between the GT and the anastomotic leakage (AL) is unclear. <b><i>Objectives:</i></b> We retrospectively evaluated the incidence of AL according to the GT shape. <b><i>Methods:</i></b> Between February 2013 and September 2017, 188 consecutive patients who underwent esophagectomy with GT reconstruction were enrolled in this cohort study. We performed GT reconstruction using a narrow GT (Gr.N) until May 2016. Subsequently, we began preparing and using a stretched GT (Gr.S). <b><i>Results:</i></b> AL occurred in 29 of 188 (15.4%) patients. The frequency of AL was lower with Gr.S than with Gr.N (<i>p</i> = 0.034). Sex, body mass index, Brinkman index, hypertension, and anemia were significantly associated with AL (<i>p</i> = 0.033, 0.041, 0.003, 0.030, and 0.042, respectively). In a multivariate logistic regression analysis, the GT shape and the Brinkman index were shown to be independent risk factors for AL (<i>p</i> = 0.016 and 0.020, respectively). <b><i>Conclusions:</i></b> The GT preparation method is an independent risk factor for AL after cervical esophagogastrostomy. Thus, improved GT preparation methods could contribute to the reduction of AL after esophagectomy.