title: Primary gastric T-cell lymphoma with and without human T-lymphotropic virus type 1.
abstract: BACKGROUND
  Gastric T-cell lymphomas are rare, and their incidence and viral status have not yet been fully clarified.
  
  
  METHODS
  Sixty-seven cases of surgically resected gastric lymphomas from city hospitals in Tokyo were evaluated. The surface phenotype was determined by immunohistochemistry, gene rearrangement by Southern blot hybridization, association with Epstein-Barr virus (EBV) by EBV-encoded small RNAs in situ hybridization, and the presence of human T-cell lymphotropic virus type 1 (HTLV-1) by serology, Southern blot hybridization, and polymerase chain reaction analysis.
  
  
  RESULTS
  Five of the 67 cases were T-cell lymphoma (7%): 3 cases were HTLV-1 negative (-) and 2 were HTLV-1 positive (+). Systemic eosinophilia was observed in the three HTLV-1(-) gastric lymphomas. Neoplastic cells were morphologically similar in both groups, but a granulomatous reaction with marked eosinophilia was observed only in the two cases of HTLV-1(-) lymphoma. They also had characteristics of natural killer (NK) cell-like T-cell lymphoma, expressing NK markers and TCRgamma gene rearrangement. Positivity with HML-1 (specific for intestinal epithelial T-cells lymphoma was observed in one HTLV-1(+) lymphoma. The EBV gene was detected in only one case of B-cell lymphoma but not in any case of T-cell lymphoma.
  
  
  CONCLUSIONS
  Gastric T-cell lymphoma occurs in 7% of gastric lymphomas in Japan and is comprised of HTLV-1-related lymphomas and lymphomas unrelated to HTLV-1, including NK cell-like lymphomas with eosinophilia.
authors.affiliation: Department of Diagnostic Pathology, Kanto Teishin Hospital, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Shimada-Hiratsuka
authors.forename: M
authors.initials: M
authors.lastname: Fukayama
authors.forename: Y
authors.initials: Y
authors.lastname: Hayashi
authors.forename: T
authors.initials: T
authors.lastname: Ushijima
authors.forename: M
authors.initials: M
authors.lastname: Suzuki
authors.forename: T
authors.initials: T
authors.lastname: Hishima
authors.forename: N
authors.initials: N
authors.lastname: Funata
authors.forename: M
authors.initials: M
authors.lastname: Koike
authors.forename: T
authors.initials: T
authors.lastname: Watanabe
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015139:Blotting, Southern; D004273:DNA, Neoplasm / Q000032:analysis; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D015329:Gene Rearrangement, T-Lymphocyte; D004854:Herpesvirus 4, Human / Q000302:isolation & purification; D015368:Human T-lymphotropic virus 1 / Q000302:isolation & purification*; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D016393:Lymphoma, B-Cell / Q000276:immunology / Q000473:pathology; D016399:Lymphoma, T-Cell / Q000276:immunology / Q000473:pathology / Q000821:virology*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011948:Receptors, Antigen, T-Cell / Q000235:genetics; D013274:Stomach Neoplasms / Q000276:immunology / Q000473:pathology / Q000821:virology*
chemical_list: D004273:DNA, Neoplasm; D004279:DNA, Viral; D011948:Receptors, Antigen, T-Cell