3525 DO GASTROESOPHAGEAL REFLUX INDUCED CHANGES IN THE SQUAMOUS MUCOSA HAVE A POSITIVE ASSOCIATION WITH THE PRESENCE OF THE INTESTINAL METAPLASIA OF BARRETT'S ESOPHAGUS?

There appears to be a close pathophysiological relationship between Barrett's esophagus and gastroesophageal reflux. In patients with GERD, pathologists often describe tissue changes of the squamous mucosa that are acknowledged as being induced by gastroesophageal reflux. PURPOSE We tested the hypothesis that histopathological reflux induced changes in squamous mucosa have a positive correlation with the presence of goblet cells or intestinal metaplasia without goblet cells in patients with endoscopic features of Barrett's esophagus. METHODS Systematic histopathological review by a single experienced gastrointestinal histopathologist (D.N.L.) of biopsy sample collections from 160 patients (143 Caucasian, median age 52 y [range 26-89], 82 males) with the endoscopical feature of gastric mucosa proximal to the gastric folds. The histopathologist specifically assessed the presence of i) goblet cells in columnar lined mucosa, ii) inflammatory infiltration in the glandular mucosa, and iii) reflux induced changes in squamous mucosa. These are Intraepithelial Eosinophils in squamous epithelium, Basal Cell Hyperplasia if basal cell layer thicker than 15% of the epithelium s thickness, Papillae & Rete Elongation if Papilla/Epithelium ratio over 2/3. For the statistical analysis we categorized the sample collections in three groups: (A) intestinal metaplasia with goblet cells, (B) intestinal metaplasia without goblet cells, and (C) no intestinal metaplasia. RESULTS The three groups (A) n=67, (B) n=36, and (C) n=57 had equally frequent inflammatory infiltration - interpreted as acute for (A) in 21%, (B) in 25%, (C) in 23% (p = 0.89); and - interpreted as chronic for (A) 22%, (B) 28%, and (C) 26% (p = 0.80). Intraepithelial Eosinophils were found in group (A) 18%, in (B) 6%, and in (C) 19% (p = 0.16). Basal Cell Hyperplasia was found in group (A) 21%, in (B) 3%, and in (C) 19% (p = 0.04). Papillae & Rete Elongation was found in group (A) 23%, in (B) 33%, and in (C) 40% (p = 0.16). CONCLUSION Gastroesophageal reflux induced changes in squamous mucosa occur at similar frequencies in patients with intestinal metaplasia containing goblet cells, intestinal metaplasia without goblet cells, and in those without intestinal metaplasia. Thus, although Barrett's esophagus is assumed to occur as a result of gastroesophageal reflux, histopathological features of reflux in squamous mucosa correspond poorly with the presence of intestinal metaplasia.