title: Specific detection of Helicobacter pylori and non-Helicobacter pylori flora in small- and large-cell primary gastric B-cell non-Hodgkin's lymphoma.
abstract: BACKGROUND
  Primary gastric non-Hodgkin's lymphomas possibly develop in response to local infection by Helicobacter pylori (H. pylori). We investigated the presence of H. pylori and non-H. pylori flora histologically in small- and large-cell primary gastric lymphoma using a specific staining method.
  
  
  METHODS
  Specimens of 52 cases of primary gastric lymphoma (17 small cell, 35 large cell) were stained with modified Giemsa (MG) and immunohistochemically using a polyclonal antibody against H. pylori (IHC).
  
  
  RESULTS
  Thirty-two cases (61.5%) (small cell 76% versus large cell 53%, P > 0.05) showed immunoreactivity for H. pylori in the mucosa surrounding the tumor. Remarkably, there was localization of H. pylori in the neck of the gastric glands in 3 cases. Non-H. pylori flora was seen in 35 cases (76.3%) (small cell 53% versus large cell 74%, P > 0.05). In 20 cases, this non-H. pylori flora was mixed with H. pylori. Five cases showed no bacterial flora at all.
  
  
  CONCLUSIONS
  (1) Using immunohistochemistry, the prevalence of gastric lymphoma cases with H. pylori (61.5%) approximates that of H. pylori in the normal population. (2) No statistical difference was found between the occurrence of H. pylori and non-H. pylori bacterial flora in small- versus large-cell lymphoma. (3) Our results suggest that H. pylori may not be the only etiologic factor in primary gastric lymphoma.
authors.affiliation: Department of Internal Medicine, University Hospital Maastricht, The Netherlands.
authors.forename: I A
authors.initials: IA
authors.lastname: Gisbertz
authors.forename: D M
authors.initials: DM
authors.lastname: Jonkers
authors.forename: J W
authors.initials: JW
authors.lastname: Arends
authors.forename: F J
authors.initials: FJ
authors.lastname: Bot
authors.forename: R W
authors.initials: RW
authors.lastname: Stockbrügger
authors.forename: L W
authors.initials: LW
authors.lastname: Vrints
authors.forename: H C
authors.initials: HC
authors.lastname: Schouten
mesh_terms: D005260:Female; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D007150:Immunohistochemistry; D018442:Lymphoma, B-Cell, Marginal Zone / Q000737:chemistry / Q000382:microbiology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000737:chemistry / Q000382:microbiology*