title: Presence of restricted killer immunoglobulin-like receptor repertoire and monoclonal T-cell receptor gamma rearrangement as evidence of mixed NK/T-cell differentiation in a subset of sinonasal lymphomas.
abstract: Most sinonasal lymphomas have a restricted killer immunoglobulin-like receptor (KIR) repertoire without a monoclonal T-cell receptor-gamma (TCR-gamma) rearrangement, implying an NK lineage. However, the lineage assignment of sinonasal lymphoma with a monoclonal TCR-gamma rearrangement is unclear because of its mixed NK/T phenotype. The possibility of a mixed NK/T lineage arises with the discovery of T cells with NK features, such as KIR(+) T cells or Valpha24(+) NKT cells. The former might transform into a T-cell lymphoma with both a monoclonal TCR-gamma rearrangement and a restricted KIR repertoire; the latter might give rise to a T-cell lymphoma with a monoclonal Valpha24 rearrangement and possibly a restricted KIR repertoire. To identify such mixed-lineage lymphomas, we undertook a survey of 15 consecutive sinonasal lymphomas and found six with both a restricted KIR repertoire and a monoclonal TCR-gamma rearrangement, consistent with KIR(+) T-cell lymphomas. Among these six cases, four female CD56(-)/CD44(-)/CD8(-)/CD45RO(+)/CD45RA(-) cases constituted a distinct group with a better prognosis than the rest of the male cases of sinonasal lymphomas. None of the six cases had a monoclonal Valpha24 repertoire, thus excluding a derivation from NKT cells. The predominance of KIR(+) T cells that normally function in chronic viral infections over Valpha24(+) NKT cells that typically recognize glycolipid antigens is consistent with the known association of Epstein-Barr virus infection with sinonasal lymphoma. The demonstration of mixed lineage in a mature lymphoid neoplasm is unusual and echoes the World Health Organization classification that placed NK-cell and T-cell lymphomas in a mixed group.
authors.affiliation: Department of Pathology, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Chung-Wu
authors.initials: CW
authors.lastname: Lin
authors.forename: Jia-Ying
authors.initials: JY
authors.lastname: Yang
authors.forename: Yi-Chun
authors.initials: YC
authors.lastname: Chuang
authors.forename: Yu-Hua
authors.initials: YH
authors.lastname: Chen
authors.forename: Maher
authors.initials: M
authors.lastname: Albitar
authors.forename: Su-Ming
authors.initials: SM
authors.lastname: Hsu
mesh_terms: D001483:Base Sequence; D002454:Cell Differentiation; D017931:DNA Primers; D015334:Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor; D006801:Humans; D007150:Immunohistochemistry; D016399:Lymphoma, T-Cell / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D009669:Nose Neoplasms / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D017931:DNA Primers