title: Enteropathy-associated T-cell lymphomas have a cytotoxic T-cell phenotype.
abstract: OBJECTIVE
  Enteropathy-associated T-cell lymphoma (EATCL) is a rare complication of coeliac disease. We investigated whether EATCLs are the neoplastic counterparts of activated cytotoxic T-cells (CTLs).
  
  
  RESULTS
  Eight cases, clinically and histologically defined, were stained with monoclonal antibodies against components of the cytotoxic granules of CTLs, granzyme B and T-cell restricted intracellular antigen (TIA-1). It was found that all cases had a cytotoxic phenotype, i.e. expression of TIA-1 in most of the tumour cells, whereas granzyme B was found in six of eight cases, mostly in a smaller number of tumour cells compared to TIA-1. Since TIA-1 and granzyme B are expressed at different stages of activation of CTLs it is hypothesized that differences in expression between granzyme B and TIA-1 in EATCL represent different stages of activation in which the tumour cells are arrested. Clinically, seven of the eight patients died within 10 months after diagnosis of EATCL.
  
  
  CONCLUSIONS
  EATCL is a clinicopathological entity with a grim prognosis and with tumour cells representing a unique neoplastic equivalent of CTLs arrested in varying stages of activation.
authors.affiliation: Department of Pathology, Free University Hospital, Amsterdam, The Netherlands.
authors.forename: P C
authors.initials: PC
authors.lastname: de Bruin
authors.forename: C E
authors.initials: CE
authors.lastname: Connolly
authors.forename: J J
authors.initials: JJ
authors.lastname: Oudejans
authors.forename: J A
authors.initials: JA
authors.lastname: Kummer
authors.forename: W
authors.initials: W
authors.lastname: Jansen
authors.forename: C F
authors.initials: CF
authors.lastname: McCarthy
authors.forename: C J
authors.initials: CJ
authors.lastname: Meijer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism; D002446:Celiac Disease / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D005260:Female; D053804:Granzymes; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D016399:Lymphoma, T-Cell / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D008875:Middle Aged; D039102:Poly(A)-Binding Proteins; D011506:Proteins; D016601:RNA-Binding Proteins / Q000378:metabolism; D012697:Serine Endopeptidases / Q000378:metabolism; D000074019:T-Cell Intracellular Antigen-1; D013602:T-Lymphocytes, Cytotoxic / Q000378:metabolism / Q000473:pathology*
chemical_list: D015703:Antigens, CD; D014408:Biomarkers, Tumor; D008565:Membrane Proteins; D039102:Poly(A)-Binding Proteins; D011506:Proteins; D016601:RNA-Binding Proteins; D000074019:T-Cell Intracellular Antigen-1; C071558:TIA1 protein, human; C509213:GZMB protein, human; D053804:Granzymes; D012697:Serine Endopeptidases