title: Nasopharyngeal/nasal type T/NK lymphomas: analysis of 14 cases and review of the literature.
abstract: OBJECTIVE
  Lymphoid malignancies expressing CD56 are rare and most occur in the nasal or nasopharyngeal region. They derive from natural killer cells or from a small subset of T cells that have granular cytoplasm containing molecules that mediate cytotoxic activity: TIA-1, granzyme B and perforin. Both types are closely associated with Epstein-Barr virus.
  
  
  METHODS
  We report the pathologic, immunophenotypic and molecular findings in 14 cases of nasopharyngeal/nasal type T/NK lymphomas.
  
  
  RESULTS
  Clinically, all patients had localized disease and also had symptoms limited to the nose. The neoplastic cells were frequently pleomorphic, and angiocentric growth was common. Combined immunophenotypic and gene rearrangement analyses demonstrated that most of the cases were true NK cell tumors and were either CD56+ and CD3- or CD56+ and CD3+. Immunohistochemical study showed TIA-1 and granzyme B expression in all cases. By in situ hybridization, most of the cases were associated to Epstein-Barr virus, harboring type 1 virus, and polymerase chain reaction amplification across the 30 bp deletion showed high frequency of latent membrane protein-1-deleted variants.
  
  
  CONCLUSIONS
  The nasal type T/NK cell lymphoma shows distinctive clinicopathologic, immunophenotypic and molecular features. These results confirm the important role of Epstein-Barr virus as a local factor in their pathogenesis.
authors.affiliation: Department of Pathology, Ramón y Cajal Hospital, Madrid, Spain.
authors.forename: Mónica
authors.initials: M
authors.lastname: García-Cosío
authors.forename: Almudena
authors.initials: A
authors.lastname: Santón
authors.forename: M Carmen
authors.initials: MC
authors.lastname: Méndez
authors.forename: Carmen
authors.initials: C
authors.lastname: Rivas
authors.forename: Carmen
authors.initials: C
authors.lastname: Martín
authors.forename: Carmen
authors.initials: C
authors.lastname: Bellas
mesh_terms: D000328:Adult; D000368:Aged; D019070:Cell Lineage; D004279:DNA, Viral; D020031:Epstein-Barr Virus Infections / Q000378:metabolism / Q000473:pathology / Q000821:virology; D005260:Female; D015321:Gene Rearrangement; D005838:Genotype; D016179:Granulocyte Colony-Stimulating Factor / Q000378:metabolism; D004854:Herpesvirus 4, Human / Q000502:physiology; D006801:Humans; D007124:Immunoenzyme Techniques; D016130:Immunophenotyping; D017403:In Situ Hybridization; D007694:Killer Cells, Natural / Q000473:pathology*; D016399:Lymphoma, T-Cell / Q000473:pathology* / Q000821:virology; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D008875:Middle Aged; D009303:Nasopharyngeal Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000821:virology; D009336:Necrosis; D009363:Neoplasm Proteins / Q000378:metabolism; D009669:Nose Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000821:virology; D054353:Perforin; D010641:Phenotype; D039102:Poly(A)-Binding Proteins; D016133:Polymerase Chain Reaction; D052899:Pore Forming Cytotoxic Proteins; D011506:Proteins; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D012269:Ribosomal Proteins; D000074019:T-Cell Intracellular Antigen-1; D013602:T-Lymphocytes, Cytotoxic / Q000473:pathology; D014763:Viral Matrix Proteins / Q000378:metabolism
chemical_list: D004279:DNA, Viral; C037662:EBV-associated membrane antigen, Epstein-Barr virus; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D009363:Neoplasm Proteins; D039102:Poly(A)-Binding Proteins; D052899:Pore Forming Cytotoxic Proteins; D011506:Proteins; D016601:RNA-Binding Proteins; D012269:Ribosomal Proteins; D000074019:T-Cell Intracellular Antigen-1; C071558:TIA1 protein, human; D014763:Viral Matrix Proteins; D054353:Perforin; C067169:RPL22 protein, human; D016179:Granulocyte Colony-Stimulating Factor