A proposal for a new validated histological definition of the gastroesophageal junction.

Present definitions of the gastroesophageal junction (GEJ) are the point of flaring of the tubular esophagus and the proximal limit of the gastric rugal folds. Neither of these has been validated as the true GEJ. This study aims to validate the location of the true GEJ using the criterion of esophageal submucosal glands. Ten esophagogastrectomy specimens, in which there was a well-defined point of flaring of the tubular esophagus that coincided with the proximal limit of gastric rugal folds, were examined by complete histological mapping to evaluate the distribution of esophageal submucosal glands and surface epithelial types. Oxyntocardiac and cardiac mucosa with or without intestinal metaplasia were present under rugal folds distal to the end of tubular esophagus in all patients to a length of 0.31 to 2.05 cm. Submucosal glands were present in the tubular esophagus and in the proximal pouch distal to the tubular esophagus in a distribution that closely coincided with squamous epithelium, oxyntocardiac, cardiac, and intestinal epithelia. Submucosal glands were never found under oxyntic mucosa. We conclude that a variable part of the saccular region distal to the tubular esophagus contains esophageal submucosal glands, therefore representing reflux-damaged distal esophagus. This results in an error, where up to 2.05 cm of distal reflux-damaged dilated esophagus can be mistaken as proximal stomach when presently accepted definitions for the GEJ are used. The true GEJ is the proximal limit of gastric oxyntic mucosa defined by histology.