Objectives: Intestinal metaplasia in Barrett's esophagus predisposes to esophageal adenocarcinoma. Intestinal metaplasia of the cardia is a common finding in persons without cancer. Many adenocarcinomas of the esophagogastric junction are large enough to obliterate any underlying intestinal metaplasia. To estimate how often adenocarcinoma of the esophagogastric junction arises in intestinal metaplasia, we studied small adenocarcinomas of the esophagogastric junction.
Methods: Resection patients had adenocarcinomas 2 cm or smaller, within 2 cm of the esophagogastric junction. Age- and sex-matched controls had resection for squamous carcinoma. Saved and new histological slides from the esophagogastric junction were examined, with additional stains.
Results: Intestinal metaplasia was found in 86% (19/22) of adenocarcinoma cases, versus 32% (7/22) of controls (p < 0.001). Intestinal metaplasia with high or low grade dysplasia was associated with 64% (14/22) of adenocarcinomas and with 5% (1/22) of controls (p < 0.001). Excluding four cases with long and three with short Barrett's esophagus, 80% (12/15) of adenocarcinomas had associated intestinal metaplasia, 53% (8/15) with dysplasia. Most adenocarcinoma cases had the incomplete type of intestinal metaplasia with a Barrett type cytokeratin 7/20 staining pattern. Helicobacter pylori were seen in one adenocarcinoma and five control cases.
Conclusions: Most adenocarcinomas of the esophagogastic junction arise in the background of intestinal metaplasia, sometimes in an endoscopically visible Barrett's esophagus, more often in small areas of intestinal metaplasia of the cardia. In cases of adenocarcinoma, the intestinal metaplasia resembled that found in Barrett's esophagus, and was not associated with H. pylori.