Gastric metaplasia of the proximal esophagus associated with esophageal adenocarcinoma and Barrett's esophagus: What is the connection?

Background/Aim: The inlet patch is an area of heterotopic gastric mucosa found in the proximal esophagus at the level of the upper esophageal sphincter. Limited data are available regarding this form of gastric metaplasia and its incidence, significance, and possible association with other esophageal diseases. We report our observations of such gastric metaplasias in patients with esophageal adenocarcinoma or Barrett's esophagus and high-grade dysplasia. Methods: All patients having Barrett's esophagus and adenocarcinoma referred for photodynamic therapy were included in this study. The patients were prospectively evaluated endoscopically for the presence of gastric metaplasia of the proximal esophagus (salmon-colored area of a least 5 mm in diameter with cardia-type gastric metaplasia on biopsy). Results: A total of 36 patients were included in this study: 11 patients with dysplastic Barrett's esophagus (8 males, mean age 79 years) and 25 adenocarcinoma patients (18 males, mean age 71 years). At endoscopy prior to photodynamic therapy, 11 patients (31%; 8 adenocarcinoma, 3 dysplastic Barrett's esophagus) were noted to have an area of gastric mucosa in the proximal esophagus. In each patient, there was at least 5 cm of normal squamous mucosa between gastric metaplasia and distal esophageal pathology. Conclusions: In this selected group of patients with high-grade dysplastic Barrett's esophagus or adenocarcinoma referred for photodynamic therapy, gastric metaplasia of the proximal esophagus was found in nearly one third. Prospective studies are under way to test more widely for this association and to determine whether this is a marker of disease severity and the result of similar pathogenetic mechanisms.