[A bronchogenic cyst of the esophageal wall--a case report and differential diagnosis from an esophageal cyst].

A 25-year-old man underwent extirpation of a cystic mass of the esophageal wall. It proved to be an unilocular cyst surrounded by a pseudo-stratified, ciliated columnar epithelium with occasional goblet cells. Outside of the epithelium, a smooth muscle layer was seen and a small foci of seromucous glands were scattered in the wall. Electron microscopic observations of the epithelial layer revealed 5 types of the cells: ciliated columnar cells, mucous cells, brush cells, intermediate cells, and basal cells. Our results suggest that electron microscopic observations are useful for distinguishing the bronchogenic cyst from the esophageal cyst. Nine cases of para-esophageal bronchogenic cysts that have been reported in Japan also are briefly reviewed.