title: Mucin pattern reflects the origin of the adenocarcinoma in Barrett's esophagus: a retrospective clinical and laboratorial study.
abstract: BACKGROUND
  Mucin immunoexpression in adenocarcinoma arising in Barrett's esophagus (BE) may indicate the carcinogenesis pathway. The aim of this study was to evaluate resected specimens of adenocarcinoma in BE for the pattern of mucins and to correlate to the histologic classification.
  
  
  METHODS
  Specimens were retrospectively collected from thirteen patients who underwent esophageal resection due to adenocarcinoma in BE. Sections were scored for the grade of intestinal metaplasia. The tissues were examined by immunohistochemistry for MUC2 and MUC5AC antibodies.
  
  
  RESULTS
  Eleven patients were men. The mean age was 61 years old (varied from 40 to 75 years old). The tumor size had a mean of 4.7 +/- 2.3 cm, and the extension of BE had a mean of 7.7 +/- 1.5 cm. Specialized epithelium with intestinal metaplasia was present in all adjacent mucosas. Immunohistochemistry for MUC2 showed immunoreactivity in goblet cells, while MUC5AC was extensively expressed in the columnar gastric cells, localizing to the surface epithelium and extending to a variable degree into the glandular structures in BE. Tumors were classified according to the mucins in gastric type in 7/13 (MUC5AC positive) and intestinal type in 4/13 (MUC2 positive). Two tumors did not express MUC2 or MUC5AC proteins. The pattern of mucin predominantly expressed in the adjacent epithelium was associated to the mucin expression profile in the tumors, p = 0.047.
  
  
  CONCLUSIONS
  Barrett's esophagus adenocarcinoma shows either gastric or intestinal type pattern of mucin expression. The two types of tumors developed in Barrett's esophagus may reflect the original cell type involved in the malignant transformation.
authors.affiliation: Department of Gastroenterology, Digestive Surgery Division, University of São Paulo School of Medicine, São Paulo, Brazil. sergioszac@gmail.com
authors.forename: Sergio
authors.initials: S
authors.lastname: Szachnowicz
authors.forename: Ivan
authors.initials: I
authors.lastname: Cecconello
authors.forename: Ulysses
authors.initials: U
authors.lastname: Ribeiro
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Iriya
authors.forename: Roberto
authors.initials: R
authors.lastname: El Ibrahim
authors.forename: Flávio Roberto
authors.initials: FR
authors.lastname: Takeda
authors.forename: Carlos Eduardo Pereira
authors.initials: CE
authors.lastname: Corbett
authors.forename: Adriana
authors.initials: A
authors.lastname: Vaz Safatle-Ribeiro
mesh_terms: D000230:Adenocarcinoma / Q000737:chemistry / Q000209:etiology* / Q000473:pathology; D000328:Adult; D000368:Aged; D001471:Barrett Esophagus / Q000150:complications*; D004938:Esophageal Neoplasms / Q000737:chemistry / Q000209:etiology* / Q000473:pathology; D005260:Female; D005753:Gastric Mucosa / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D055271:Mucin 5AC / Q000032:analysis*; D055262:Mucin-2 / Q000032:analysis*; D012189:Retrospective Studies
chemical_list: C524625:MUC2 protein, human; C524678:MUC5AC protein, human; D055271:Mucin 5AC; D055262:Mucin-2