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Incidence of heterotopic gastric mucosa in the upper oesophagus.

In a prospective study of the frequency and clinical importance of heterotopic gastric mucosa in the upper oesophagus, 634 consecutive veteran patients (98% male), undergoing endoscopy for various gastrointestinal complaints, were evaluated. Sixty four patients (10%) had heterotopic gastric mucosal patches varying in size from 0.2-0.3 cm to 3 x 4-5 cm often immediately below the upper oesophageal sphincter. Biopsies of these patches showed fundic type gastric mucosa with chief and parietal cells. The 10% prevalence is more than twice the highest reported prevalence rate of endoscopically detected patches in the upper oesophagus. The characteristic location of these patches at the sphincter area, their uniformly fundic type gastric mucosa, and their poor correlation with clinical and endoscopic evidence of gastro-oesophageal reflux support the hypothesis that they are congenital in nature.