Expression of cyclooxygenase-2 in the remnant esophageal mucosa after esophagectomy with anti-reflux anastomosis

Objective To investigate the significance of cyclooxygenase-2 (COX-2) expression in the remnant esophageal mucosa after esophagectomy with modified Nissen folding anastomosis. Methods From December 2013 to July 2015, 50 patients with lower esophageal cancer who underwent thoracic surgery were divided into anti-reflux anastomosis group and conventional anastomosis group according to the principle of randomized controlled trial. The conventional anastomosis group was performed with esophageal cancer resection and esophagogastric anastomosis. The anti-reflux anastomosis group was modified with Nissen folding on the basis of anastomosis anastomosis. 42 patients were followed up, and 10 healthy volunteers without reflux symptoms were enrolled as the control group. Morphological changes and mucosal biopsy of residual esophageal mucosa were observed by gastroscopy. The expression of COX-2 gene in residual esophageal mucosa was detected by real-time PCR. Results The incidence of reflux esophagitis in the anti-reflux anastomosis group was 45%, and that in the conventional anastomosis group was 68.2%. There was no significant difference in the incidence of reflux esophagitis between the two groups (P=1.313), while the score of reflux esophagitis in the anti-reflux group was significantly lower than that in the conventional group (P=0.038). The COX-2 expression of the esophageal mucosa in the control group was low, and the expression in the other two groups was higher than that in the control group (P=0.031, P=0.016). But there were no significant differences between these two groups (P=0.137). The COX-2 expression on the residual esophageal mucosa in the conventional anastomosis group and the anti-reflux anastomosis group was higher than that in the control group (P=0.002, P=0.047), while the expression in the anti-reflux anastomosis group was significantly lower than that in the conventional anastomosis group (P=0.036). Conclusions Esophageal cancer resection with modified Nissen folding has anti-reflux effect. Detection of COX-2 expression in residual esophageal mucosa is a sensitive indicator for postoperative gastroesophageal reflux in esophageal cancer, which is also a new method for evaluating the effect of anti-reflux anastomosis. Key words: Esophageal carcinoma; Anti-reflux surgery; Reflux esophagitis; Gastroesophageal reflux; Cyclooxygenase-2