Cytokeratin 7 and 20 expression in intestinal metaplasia of the distal oesophagus: relationship to gastro‐oesophageal reflux disease

Abstract

Intestinal metaplasia and gastro-oesophageal reflux disease typify classical Barrett's oesophagus. Cytokeratin (CK) 7 and 20 phenotypes differentiate intestinal metaplasia in long segment Barrett's oesophagus from gastric intestinal metaplasia. This study examines the relationship between CK7/20 phenotypes and reflux disease in intestinal metaplasia of the distal oesophagus. Eighty patients with oesophageal pH studies included 30 with long segment Barrett's, 16 with short segment Barrett's and 34 with intestinal meatplasia of the gastro-oesophageal junction. Representative biopsy specimens were immunostained for CK7 and CK20. All 30 long segment patients demonstrated a Barrett's CK7/20 phenotype. All nine short segment patients with gastro-oesophageal reflux had a Barrett's CK7/20 phenotype, while four of seven short segment patients without reflux had a gastric CK7/20 phenotype (P = 0.019). Of 14 patients with intestinal metaplasia of the gastro-oesophageal junction and reflux, 10 (71%) had a Barrett's CK7/20 phenotype, compared with 11 (55%) of the 20 non-reflux patients. CK7/20 immunoreactivity for patients with intestinal metaplasia of the distal oesophagus without long segment Barrett's oesophagus suggests a heterogeneous group, with an association between Barrett's CK7/20 pattern and gastro-oesophageal reflux disease in both short segment Barrett's and intestinal metaplasia of the gastro-oesophageal junction.