title: [Helicobacter pylori genotypes of gastrointestinal B cell lymphoma].
abstract: OBJECTIVE
  To assess the expression of specific virulence-associated Helicobacter pylori (Hp) genotypes. (cag A, vac A, and ice A status) in primary gastrointestinal B cell lymphoma.
  
  
  METHODS
  Forty-nine paraffin wax embedded tissues were analyzed by immunohistochemical staining and polymerase chain reaction.
  
  
  RESULTS
  There were 14 cases of mucosa associated lymphoid tissue lymphoma (MALT-L) (8 in stomach, and 6 in intestine) and 35 cases of diffuse large B cell lymphoma (DLBCL) (21 in stomach, and 14 in intestine) in all. The positive rates of vac A s1, vac A s2, vac A m2, ice A 1 and cag A were 50.0%, 42.9%, 50.0%, 14.3% and 85.7% in MALT-L; 57.1%, 40.0%, 25.7%, 5.7% and 91.4% in DLBCL, respectively.
  
  
  CONCLUSIONS
  High toxicity cag A+Hp strains seem to play a role in the pathogenesis of gastrointestinal B cell lymphoma, whereas vac A m2 may be more associated with MALT-L. Clinical stage was not associated with virulence-associated Hp genotypes.
authors.affiliation: Department of Pathology, Peking University First Hospital, Beijing 100034, China. yinhf@hotmail.com
authors.forename: Hong-fang
authors.initials: HF
authors.lastname: Yin
authors.forename: Ting
authors.initials: T
authors.lastname: Li
mesh_terms: D005838:Genotype; D016480:Helicobacter pylori / Q000235:genetics* / Q000472:pathogenicity; D006801:Humans; D016393:Lymphoma, B-Cell / Q000382:microbiology* / Q000473:pathology; D018442:Lymphoma, B-Cell, Marginal Zone / Q000382:microbiology / Q000473:pathology; D016403:Lymphoma, Large B-Cell, Diffuse / Q000382:microbiology / Q000473:pathology; D009367:Neoplasm Staging; D013274:Stomach Neoplasms / Q000382:microbiology* / Q000473:pathology