title: Aberrant antigenic expression in extranodal NK/T-cell lymphoma: a multi-parameter study from Thailand.
abstract: BACKGROUND
  Extranodal NK/T-cell lymphoma, nasal type (ENKTL) is not common worldwide, but it is the most common T- and NK-cell lymphomas in many Asian countries. Immunophenotypic profiles were studied based on limited series. The authors, therefore, studied on ENKTL according to characterize immunophenotypic profiles as well as the distribution of EBV subtype and LMP-1 gene deletion.
  
  
  METHODS
  By using tissue microarray (TMA), immunohistochemical study and EBV encoded RNA (EBER) in situ hybridization were performed. T-cell receptor (TCR) gene rearrangement, EBV subtyping, and LMP-1 gene deletion were studied on the available cases.
  
  
  RESULTS
  There were 22 cases eligible for TMA. ENKTL were positive for CD3 (91%), CD5 (9%), CD7 (32%), CD4 (14%), CD56 (82%), TIA-1 (100%), granzyme B (95%), perforin (86%), CD45 (83%), CD30 (75%), Oct2 (25%), and IRF4/MUM1 (33%). None of them was positive for βF1, CD8, or CD57. TCR gene rearrangement was negative in all 18 tested cases. EBV was subtype A in all 15 tested cases, with 87% deleted LMP-1 gene. Cases lacking perforin expression demonstrated a significantly poorer survival outcome (p = 0.008).
  
  
  CONCLUSIONS
  The present study demonstrated TIA-1 and EBER as the two most sensitive markers. There were a few CD3 and/or CD56 negative cases noted. Interestingly, losses of CD45 and/or CD7 were not uncommon while Oct2 and IRF4/MUM1 could be positive in a subset of cases. Based on the present study in conjunction with the literature review, determination of PCR-based TCR gene rearrangement analysis might not be a useful technique for making diagnosis of ENKTL.
authors.affiliation: Department of Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Thailand. watpptp@yahoo.com
authors.forename: Tawatchai
authors.initials: T
authors.lastname: Pongpruttipan
authors.forename: Tanawan
authors.initials: T
authors.lastname: Kummalue
authors.forename: Anan
authors.initials: A
authors.lastname: Bedavanija
authors.forename: Archrob
authors.initials: A
authors.lastname: Khuhapinant
authors.forename: Koichi
authors.initials: K
authors.lastname: Ohshima
authors.forename: Fumiko
authors.initials: F
authors.lastname: Arakawa
authors.forename: Daisuke
authors.initials: D
authors.lastname: Niino
authors.forename: Sanya
authors.initials: S
authors.lastname: Sukpanichnant
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics; D000293:Adolescent; D000328:Adult; D000368:Aged; D001706:Biopsy; D003598:Cytoskeletal Proteins / Q000235:genetics; D005260:Female; D017353:Gene Deletion; D015329:Gene Rearrangement, T-Lymphocyte; D019672:Genes, T-Cell Receptor; D004854:Herpesvirus 4, Human / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D060588:LIM Domain Proteins / Q000235:genetics; D054391:Lymphoma, Extranodal NK-T-Cell / Q000175:diagnosis* / Q000235:genetics / Q000276:immunology / Q000628:therapy / Q000821:virology; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D011379:Prognosis; D012367:RNA, Viral / Q000302:isolation & purification; D013785:Thailand; D046888:Tissue Array Analysis; D055815:Young Adult
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D003598:Cytoskeletal Proteins; D060588:LIM Domain Proteins; C484380:PDLIM7 protein, human; D012367:RNA, Viral