Extension of squamous epithelium into the proximal stomach: a newly recognized mucosal abnormality

The presence of squamous epithelium in the stomach has been rarely noted in the past with only sporadic case reports of squamous cell carcinoma of the stomach and a variety of other pathological processes. We report the documentation, over a period of 9 months, of squamous epithelium extending beyond the esophagogastric junction and into the proximal stomach in 16 patients who underwent upper endoscopy.

This newly recognized mucosal abnormality was systematically identified by both antegrade and retrograde views of the esophagogastric junction during routine upper endoscopy. Other associated mucosal abnormalities were also evaluated (Barrett's esophagus, erosive esophagitis, etc.). Biopsies were obtained from the distal esophagus, cardia, antrum and the squamous extension. Additionally, all patients underwent a detailed interview.

Of the patients, 14 were Caucasian and two Hispanic; all were males, with a mean age 61.2+/-4.2. Indications for upper endoscopy included dysphagia, Barrett's esophagus surveillance, failure of antireflux treatment and anemia. Heartburn was reported by 12 patients (75%). None of the patients reported a history of corrosive injury, foreign body ingestion or surgery. A total of 12 patients had a solitary tongue of squamous cell extension, three had two tongues and in addition, two had squamous islands. Hiatal hernia was present in all patients, Barrett's esophagus in six (37.5 %), and esophageal stricture in four.

Squamous cell extension into the proximal stomach is a newly recognized mucosal abnormality with presently unknown clinical significance. This mucosal abnormality may represent an esophageal mucosal response to proximal gastric injury.