title: Ki67 expression in different epithelial types in columnar lined oesophagus indicates varying levels of expanded and aberrant proliferative patterns.
abstract: OBJECTIVE
  To evaluate proliferative patterns in metaplastic columnar epithelia of the oesophagus, classified as oxynto-cardiac (n = 43), cardiac (n = 45) intestinal without dysplasia (n = 41), dysplastic intestinal epithelium (n = 25), and adenocarcinoma (n = 15) by Ki67 immunohistochemistry.
  
  
  RESULTS
  Abnormal patterns of Ki67 immunoreactivity were classified into (i) expanded proliferation, characterized by increased levels of Ki67 expression in the deep and mid third of the foveolar pit; and (ii) aberrant proliferation, characterized by positive staining in the surface epithelium and superficial third of the foveolar pit. A significant step-wise increase in the frequency of expanded proliferation was seen in oxynto-cardiac, cardiac, intestinal and dysplastic intestinal epithelium indicative of increasing levels of damage. Aberrant proliferation was absent in oxynto-cardiac mucosa, present at a low and similar level in cardiac, intestinal and low-grade dysplastic epithelia and at a significantly increased frequency in high-grade dysplasia.
  
  
  CONCLUSIONS
  These findings suggest that oxynto-cardiac mucosa occurs in a low damage environment and intestinal metaplasia in a high damage environment along the length of the columnar lined oesophageal segment. Aberrant proliferative patterns with Ki67 staining are not useful in differentiating reactive epithelia from low-grade dysplasia, but may prove useful in the diagnosis of high-grade dysplasia.
authors.affiliation: Department of Pathology, Los Angeles County/University of Southern California Medical Center, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
authors.forename: M
authors.initials: M
authors.lastname: Olvera
authors.forename: K
authors.initials: K
authors.lastname: Wickramasinghe
authors.forename: R
authors.initials: R
authors.lastname: Brynes
authors.forename: X
authors.initials: X
authors.lastname: Bu
authors.forename: Y
authors.initials: Y
authors.lastname: Ma
authors.forename: P
authors.initials: P
authors.lastname: Chandrasoma
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology; D001471:Barrett Esophagus / Q000378:metabolism / Q000473:pathology; D049109:Cell Proliferation; D003937:Diagnosis, Differential; D004848:Epithelium / Q000737:chemistry / Q000473:pathology; D004938:Esophageal Neoplasms / Q000378:metabolism / Q000473:pathology; D004947:Esophagus / Q000737:chemistry / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000032:analysis*
chemical_list: D019394:Ki-67 Antigen