title: Differences in the definitions used for esophageal and gastric diseases in different countries: endoscopic definition of the esophagogastric junction, the precursor of Barrett's adenocarcinoma, the definition of Barrett's esophagus, and histologic criteria for mucosal adenocarcinoma or high-grade dysplasia.
abstract: BACKGROUND
  Definitions and opinions in the field of gastroenterology vary widely in different countries.
  
  
  METHODS
  Here we discuss four such important differences: the definition of the esophagogastric junction (EGJ), the possible precursor of Barrett's adenocarcinoma, the definition of Barrett's esophagus (BE), and the histologic criteria for mucosal adenocarcinoma. In addition, we consider which definitions and opinions might be valid and practical.
  
  
  RESULTS
  There are two different endoscopic definitions of the EGJ. Our research on German subjects has indicated that many small Barrett's adenocarcinomas may arise not in the intestinal-type but in the cardiac-type mucosa. If an area of columnar-lined esophagus (CLE) is only partially involved by intestinal metaplasia, then the latter cannot always be demonstrated in biopsy specimens. Therefore, we do not think that a definition of BE as CLE with histologic intestinal metaplasia is practical. Data from the literature have shown that many cases of high-grade dysplasia (HGD) progress to carcinoma within a very short time, and in most such cases the carcinoma has been underdiagnosed in biopsy specimens as HGD.
  
  
  CONCLUSIONS
  With regard to the definitions and opinions, an exchange of views between gastroenterologists in North America, Europe, and Japan would be desirable.
authors.affiliation: Research Team for Geriatric Pathology, Tokyo Metropolitan Institute of Gerontology and Department of Pathology, Tokyo Metropolitan Geriatric Hospital, Tokyo, Japan. takubo@tmig.or.jp
authors.forename: Kaiyo
authors.initials: K
authors.lastname: Takubo
authors.forename: Michael
authors.initials: M
authors.lastname: Vieth
authors.forename: Junko
authors.initials: J
authors.lastname: Aida
authors.forename: Motoji
authors.initials: M
authors.lastname: Sawabe
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Kumagai
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Hoshihara
authors.forename: Tomio
authors.initials: T
authors.lastname: Arai
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis*; D001471:Barrett Esophagus / Q000175:diagnosis*; D004938:Esophageal Neoplasms / Q000175:diagnosis*; D004943:Esophagogastric Junction / Q000473:pathology; D004945:Esophagoscopy; D005762:Gastroenterology / Q000592:standards*; D005773:Gastroscopy; D006801:Humans; D011230:Precancerous Conditions / Q000175:diagnosis*; D013274:Stomach Neoplasms / Q000175:diagnosis; D009626:Terminology as Topic