title: Cytokeratin and DAS-1 immunostaining reveal similarities among cardiac mucosa, CIM, and Barrett's esophagus.
abstract: OBJECTIVE
  The normal histology at the gastroesophageal junction, and in particular the nature of cardiac mucosa, remains in dispute. Likewise, the relationship of intestinal metaplasia at the gastroesophageal junction (CIM) to Barrett's and intestinal metaplasia of the stomach (GIM) is unclear. The aim of this study was to assess the immunostaining characteristics of cardiac mucosa and CIM and compare their staining pattern with that of other foregut mucosal types. We hypothesized that the immunostaining patterns of these foregut tissues would provide insight into the nature and etiology of cardiac mucosa and CIM.
  
  
  METHODS
  Paraffin-embedded biopsy specimens from 50 patients with normal antral or fundic mucosa, cardiac mucosa, squamous mucosa, CIM, GIM, or Barrett's were obtained and immunostained with a panel of monoclonal antibodies including those for cytokeratins 7 and 20 (CK7/CK20) and DAS-1.
  
  
  RESULTS
  Biopsies from normal gastric antral and fundic mucosa and squamous esophageal mucosa all showed a non-Barrett's type CK7/CK20 immunostaining pattern, whereas in 85% of patients, cardiac mucosa had a Barrett's type CK7/CK20 pattern (p < 0.001). A Barrett's type CK7/ CK20 staining pattern was seen in 100% of Barrett's, 78% of CIM, and 0% of GIM patients. Likewise, DAS-1 staining was similar in patients with CIM and Barrett's and significantly different in patients with GIM.
  
  
  CONCLUSIONS
  Cytokeratin immunostaining of cardiac mucosa demonstrates significant differences from recognized normal gastric and esophageal mucosa but a similarity to Barrett's. This suggests that cardiac mucosa, like Barrett's, may be acquired. Likewise, immunostaining similarities between CIM and Barrett's biopsies point to the possibility of a reflux etiology for CIM in some patients.
authors.affiliation: Department of Cardiothoracic Surgery, The University of Southern California, Keck School of Medicine, Los Angeles, USA.
authors.forename: Steven R
authors.initials: SR
authors.lastname: DeMeester
authors.forename: Kumari S
authors.initials: KS
authors.lastname: Wickramasinghe
authors.forename: Reginald V N
authors.initials: RV
authors.lastname: Lord
authors.forename: Adam
authors.initials: A
authors.lastname: Friedman
authors.forename: Nagammapudur S
authors.initials: NS
authors.lastname: Balaji
authors.forename: Parakrama T
authors.initials: PT
authors.lastname: Chandrasoma
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Hagen
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Peters
authors.forename: Tom R
authors.initials: TR
authors.lastname: DeMeester
mesh_terms: D000906:Antibodies / Q000032:analysis*; D001471:Barrett Esophagus / Q000150:complications / Q000378:metabolism* / Q000473:pathology; D001706:Biopsy; D002299:Cardia / Q000378:metabolism* / Q000473:pathology; D004943:Esophagogastric Junction / Q000378:metabolism* / Q000473:pathology; D005748:Gastric Fundus / Q000737:chemistry / Q000473:pathology; D016481:Helicobacter Infections / Q000150:complications / Q000473:pathology; D016480:Helicobacter pylori; D006801:Humans; D007150:Immunohistochemistry; D007381:Intermediate Filament Proteins / Q000032:analysis*; D053554:Keratin-20; D053552:Keratin-7; D007633:Keratins / Q000032:analysis*; D008679:Metaplasia; D009092:Mucous Membrane / Q000378:metabolism / Q000473:pathology; D011706:Pyloric Antrum / Q000737:chemistry / Q000473:pathology
chemical_list: D000906:Antibodies; C467479:DAS-1 protein, human; D007381:Intermediate Filament Proteins; C507499:KRT20 protein, human; C507497:KRT7 protein, human; D053554:Keratin-20; D053552:Keratin-7; D007633:Keratins