Cardiac rather than intestinal-type background in endoscopic resection specimens of minute Barrett adenocarcinoma

Summary Many publications focusing on the background or original mucosa of Barrett adenocarcinoma have maintained that adenocarcinoma arises in intestinal-type mucosa with goblet cells in the columnar-lined esophagus, and this has become a central dogma. The mucosa on each side of a series of 141 minute esophageal adenocarcinomas (almost all of which were mucosal carcinomas) resected by endoscopic mucosal resection was recorded as the background mucosa. All 141 cases had endoscopic evidence of an esophageal origin, and for 113 of them, histologic evidence of an esophageal origin was also available. The mucosae were classified into 4 types—squamous, cardiac, fundic, and intestinal—based on routine histology and immunohistochemical staining. The present joint pathologic examination of the background mucosa of Barrett adenocarcinoma conducted by Japanese and German pathologists and gastroenterologists found that more than 70% of primary small adenocarcinomas (