Mo1817 Dysplasia in the Gastric Cardia Is Not Uncommon Among Patients Who Are Successful Treated by Radiofrequency Ablation for Dysplastic Barrett's Esophagus -A Prospective Study

Abstract

Background: Radiofrequency ablation (RFA) is effective and safe for eradicating dysplasia and intestinal metaplasia (IM) in patients with dysplastic Barrett's esophagus (BE). However, dysplasia or early cancer has been reported in the gastric cardia of patients who achieved complete eradication of intestinal metaplasia (CEIM). Our aim was to determine the prevalence of dysplasia in the endoscopically normal gastric cardia of patients who achieved CEIM in a tertiary care center. Methods: We performed a prospective cohort study of patients treated with RFA for BE who achieved CEIM at the University of North Carolina between 2012 and 2013. Data including demographics, medical history, worst histology, endoscopy findings, and complications were recorded on standardized case report forms. CEIM was defined as complete endoscopic resolution and at least one esophageal biopsy session after RFA demonstrating no IM. To assess for cardiac dysplasia, standard high resolution and narrow band imaging was performed. Then, a standardized study biopsy protocol, which included 4 quadrant biopsies at the top of the gastric folds, 1 cm into the cardia and 2 cm into the cardia (12 biopsies total) was utilized. The main outcome, the prevalence of dysplasia in the gastric cardia among patients who achieved CEIM, was calculated for the entire cohort and stratified by pre-treatment histology. Parametric and non-parametric tests were used to compare the baseline characteristics of patients who had dysplasia in gastric cardia versus patients without dysplasia. Results: 59 patients who achieved CEIM were prospectively enrolled. Of these patients, 4 (6.8%) demonstrated dysplasia in the gastric cardia. Three of these four patients had endoscopically normal appearing cardia; 1 patient had gastric nodularity. The demographic and BE baseline characteristics of patients who had dysplasia in gastric cardia were not significantly different from patients who did not demonstrate dysplasia (Table). When stratified by worst histology prior to RFA, the prevalence of dysplasia in the gastric cardia among patients who achieved CEIM was 6.3% (1 out of 16) for patients with low-grade dysplasia, 5.7% (2 out of 35) for patients with high-grade dysplasia, and 12.5% (1 out of 8) for patients with intramucosal carcinoma. The prevalence of gastric dysplasia did not differ by worst pre-treatment BE histology (P=0.770). Conclusions: Dysplasia in the endoscopically normal gastric cardia following successful eradication of dysplastic BE is not uncommon, with an overall prevalence of 6.8%.Most cases did not have visible nodularity endoscopically. The prevalence does not differ by worst BE histology prior to RFA treatment. Routine endoscopic surveillance of post-ablation patients achieving complete eradication of intestinal metaplasia should include routine surveillance gastric cardia biopsies. The characteristics of patients with dysplasia in gastric cardia vs. patients without dysplasia in gastric cardia