The presence and mucin histochemistry of cardiac type mucosa at the esophagogastric junction.

Abstract

Traditionally, the gastric cardia has been described as a native part of the stomach connecting to the esophagus. In recent literature, however, it is suggested that the cardia is an acquired lesion that develops due to gastroesophageal reflux disease. As a contribution to this debate, we evaluated the presence of cardiac mucosa at the esophagogastric junction (EGJ) in a random group of patients who presented at our endoscopy unit. In 253 unselected patients, biopsies were taken from the EGJ. In order to prevent sampling error, we selected only those EGJ biopsies in which the squamocolumnar junction (SCJ) was present in the histological biopsy material. Fifty-five patients were excluded since the SCJ was located proximal to the EGJ in the esophagus. The type of columnar mucosa immediately distal to the SCJ, and its mucin histochemistry, were assessed. The columnar mucosa was categorized as purely cardiac, oxyntocardiac, or fundic mucosa. In 63 of the 198 patients, the SCJ was actually present in the EGJ biopsies. Purely cardiac mucosa was present in 39 (62%) biopsies and oxyntocardiac mucosa was present in 24 (38%) biopsies. Fundic mucosa was not seen directly adjacent to squamous epithelium. Acid mucins were present in 23 (37%) patients and they correlated with histological esophagitis and presence of H. pylori in the cardia. Cardiac mucosa was uniformly present adjacent to the squamous epithelium at the EGJ. This argues against the hypothesis that the gastric cardia is an acquired metaplastic lesion. The presence of acid mucins was frequently observed and could be a pathological condition as it was associated with histological esophagitis and the presence of H. pylori in the cardia.