title: Mucin phenotypic expression and background mucosa of esophagogastric junctional adenocarcinoma.
abstract: BACKGROUND
  In the West, the incidence of adenocarcinoma of the cardia or esophagogastric junction (EGJ) is increasing. This carcinoma is variously defined, however, and it contains heterogeneous tumors. In Japan, the frequency of this carcinoma is low, and little is known about it. We studied small esophagogastric junctional adenocarcinoma to determine its characteristics in Japanese patients.
  
  
  METHODS
  Fifty-four patients with Siewert type II junctional adenocarcinoma (with tumors <<4 cm in maximum diameter) were studied. The carcinomas were classified into two types: tumors straddling the EGJ (EGJ-type) and tumors occurring entirely below the EGJ (bEGJ-type). Characteristics of the tumors and surrounding mucosae were evaluated. Phenotypic expression of mucin, p53 overexpression, and Helicobacter pylori infection were investigated histologically and immunohistochemically.
  
  
  RESULTS
  Twenty-three (43%) patients had EGJ-type and 31 (57%) had bEGJ-type carcinomas. The ratio of advanced cancers was significantly higher in EGJ-type. Some between-group similarities and differences existed in histological type, mucin phenotype, and p53 protein overexpression, but they were not statistically significant. In the mucosa surrounding EGJ-type tumors vs bEGJ-type tumors, oxyntic glands were significantly better preserved, gastric intestinal metaplasia occurred significantly less frequently, and the H. pylori infection rate was lower. Barrett's metaplasia was seen in only 2 patients, with the EGJ-type.
  
  
  CONCLUSIONS
  EGJ-type and bEGJ-type adenocarcinomas have different background mucosa of the stomach. EGJ-type has less atrophy of the oxyntic glands and less intestinal metaplasia in the stomach. This type appears to be the Western-type junctional adenocarcinoma that is still rare in Japan. Many cases of advanced junctional adenocarcinoma in Japan are of subjunctional origin.
authors.affiliation: Department of Pathology, Osaka Medical Center for Cancer and Cardiovascular Diseases, 1-3-3 Nakamichi, Higashinari-ku, Osaka 537-8511, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Tsuji
authors.forename: Shingo
authors.initials: S
authors.lastname: Ishiguro
authors.forename: Yoshitane
authors.initials: Y
authors.lastname: Tsukamoto
authors.forename: Masayuki
authors.initials: M
authors.lastname: Mano
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Kasugai
authors.forename: Isao
authors.initials: I
authors.lastname: Miyashiro
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Doki
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Iishi
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Kudo
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D000368:Aged; D000369:Aged, 80 and over; D001471:Barrett Esophagus / Q000235:genetics / Q000473:pathology; D004943:Esophagogastric Junction / Q000473:pathology*; D005260:Female; D005752:Gastric Mucins / Q000032:analysis / Q000235:genetics*; D005753:Gastric Mucosa / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D013274:Stomach Neoplasms / Q000235:genetics* / Q000473:pathology; D016159:Tumor Suppressor Protein p53 / Q000032:analysis
chemical_list: D005752:Gastric Mucins; D016159:Tumor Suppressor Protein p53