title: Classification of cell lineage and anatomical site, and prognosis of extranodal T-cell lymphoma -- natural killer cell, cytotoxic T lymphocyte, and non-NK/CTL types.
abstract: Due to their minority among the non-Hodgkin lymphomas, classification of extranodal T-cell lymphomas, including those of the natural killer (NK) cell type, has long been controversial and unclear, and the clinical outcome is not well clarified. Recently, new well-defined disease entities have been described based on tumor cell biology combined with anatomical site, clinical features, Epstein-Barr virus (EBV) status, and cell lineage as determined by immunophenotype and genotype. Cytological features are usually not specific, and there are no morphologic correlates with the classification of extranodal T/NK-cell lymphomas. From a human T-cell lymphotropic virus type 1 (HTLV-1) endemic area in Japan, we report here the analysis of 144 cases of extranodal T-cell lymphoma, from which fresh tissues were available. As the clinicopathological features were known, we simply reclassified the cases according to cell lineage and anatomical site. The extranodal T-cell lymphomas were classified into three types on the basis of cell lineage: (1) natural killer cell (NK) type [sCD3-, CD56+, T-cell receptor gene (TCR) germline], (2) cytotoxic T lymphocyte (CTL) type [sCD3+, TIA-1+, TCR rearranged, CD8+/-, CD4-/+], and (3) non-NK/CTL type [sCD3+, TIA-1-, TCR rearranged, CD4+/-, CD8-/+]. In addition to cell lineage, the anatomical site and clinical features were added for subclassification. NK type tumors (35 cases) included the lymphoblastic type, nasal/nasal-type NK lymphoma, and NK leukemia. The CTL type (46 cases) included anaplastic large cell lymphoma (ALCL), cutaneous type, intestinal, gamma delta T-cell type, and an unspecified type. The non-NK/CTL type (63 cases) included adult T-cell leukemia/lymphoma (ATLL), mycosis fungoides (MF), and an unspecified type. With the exception of ATLL and MF, most extranodal T-cell lymphomas had a cytotoxic phenotype of NK type or CTL type and were often associated with EBV infection. MF and the unspecified type within the non-NK/CTL tumors, with the exception of ATLL, had a favorable prognosis. However, NK and CTL types, with the exception of ALCL, were associated with a poor prognosis. Our results indicate that anatomical site and cell lineage are useful predictors of clinical outcomes of extranodal T-cell lymphomas.
authors.affiliation: Department of Pathology, School of Medicine, Fukuoka University, Nanakuma 7-45-1, Jonanku, Fukuoka 814-01, Japan. ohshima@fukuoka-u.ac.jp
authors.forename: Koichi
authors.initials: K
authors.lastname: Ohshima
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Koga
authors.forename: Junji
authors.initials: J
authors.lastname: Suzumiya
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kikuchi
mesh_terms: D015703:Antigens, CD / Q000378:metabolism; D014408:Biomarkers, Tumor / Q000378:metabolism; D015139:Blotting, Southern; D019070:Cell Lineage; D004273:DNA, Neoplasm / Q000032:analysis; D004279:DNA, Viral / Q000032:analysis; D020031:Epstein-Barr Virus Infections / Q000150:complications / Q000473:pathology; D015490:HTLV-I Infections / Q000150:complications / Q000473:pathology; D004854:Herpesvirus 4, Human / Q000235:genetics / Q000302:isolation & purification; D015368:Human T-lymphotropic virus 1 / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D007150:Immunohistochemistry; D007694:Killer Cells, Natural / Q000378:metabolism / Q000473:pathology*; D016399:Lymphoma, T-Cell / Q000145:classification* / Q000401:mortality / Q000473:pathology; D011379:Prognosis; D012367:RNA, Viral / Q000032:analysis; D012189:Retrospective Studies; D016019:Survival Analysis; D015996:Survival Rate; D013602:T-Lymphocytes, Cytotoxic / Q000378:metabolism / Q000473:pathology*
chemical_list: D015703:Antigens, CD; D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D004279:DNA, Viral; C099537:Epstein-Barr virus encoded RNA 1; D012367:RNA, Viral