Histopathological features of the esophagogastric junction

The esophagogastric junction has diverse histological features including cardiac mucosa, pancreatic acinar metaplasia, and squamous metaplasia-like change. Esophageal cardiac glands are scattered in the lamina propria, predominating in the distal esophagus. It was suggested that cardiac and oxyntocardiac mucosa were not normally present and, when present, represented pathological metaplastic epithelia resulting from reflux damage of squamous epithelium. This hypothesis has created a great deal of controversy, which has not yet been resolved. Moreover, the extent of the cardiac mucosa itself has recently become a focus of interest. Our results showed the high incidence of cardiac mucosa. The pathogenesis of pancreatic acinar cells has been the subject of considerable speculation. Pancreatic acinar cells have been reported in the gastric mucosa of pediatric subjects, suggesting a congenital origin, whereas in other reports the presence of pancreatic heterotopia has almost invariably been associated with inflammation and atrophy. Squamous metaplasia-like change, also known as multilayered epithelium, which resembles the cervical transformation zone, is composed of multiple layers of basally located flattened squamoid cells covered by columnar mucous cells. In some reports, it was concluded that multilayered epithelium as a precursor of Barrett's mucosa. However, there was an opinion that squamous metaplasia-like change or multilayered epithelium was only a metaplasia that was sometimes seen at the esophagogastric junction (EGJ). © 2006 Japan Esophageal Society and Springer-Verlag.