title: Immunophenotypic and antigen receptor gene rearrangement analysis in T cell neoplasia.
abstract: The author reviews the immunophenotypic profiles displayed by the major clinicopathologic categories of T cell neoplasia, the immunophenotypic criteria useful in the immunodiagnosis of T cell neoplasia, and the contributions made by antigen receptor gene rearrangement analysis to the understanding of T cell neoplasia. Neoplasms belonging to distinct clinicopathologic categories of T cell neoplasia often exhibit characteristic immunophenotypic profiles. Approximately 80% of lymphoblastic lymphomas and 20% of acute lymphoblastic leukemias express phenotypes consistent with prethymic and intrathymic stages of T cell differentiation, including intranuclear terminal deoxynucleotidyl transferase. Cutaneous T cell lymphomas of mycosis fungoides type usually express pan-T cell antigens CD2, CD5, and CD3, often lack the pan-T cell antigen CD7, and usually express the mature, peripheral helper subset phenotype, CD4+ CD8-. Cutaneous T cell lymphomas of nonmycosis fungoides type and peripheral T cell lymphomas often lack one or more pan-T cell antigens and, in addition, occasionally express the anomalous CD4+ CD8+ or CD4- CD8- phenotypes. T gamma-lymphoproliferative disease is divisable into two broad categories: those cases that are CD3 antigen positive and exhibit clonal T cell receptor beta chain (TCR-beta) gene rearrangements and those cases that are CD3 antigen negative and exhibit the TCR-beta gene germline configuration. Human T cell lymphotropic virus-I (HTLV-I) associated Japanese, Carribean, and sporadic adult T cell leukemia/lymphomas usually express pan-T cell antigens, the CD4+ CD8- phenotype, and various T cell-associated activation antigens, including the interleukin-2 receptor (CD25). Immunophenotypic criteria useful in the immunodiagnosis of T cell neoplasia include, in increasing order of utility, T cell predominance, T cell subset antigen restriction, anomalous T cell subset antigen expression, and deletion of one or more pan-T cell antigens. Only in exceptional circumstances do normal, non-neoplastic T cell populations express the CD4- CD8- or the CD4+ CD8+ phenotype and/or lack one or more pan-T cell antigens. T cell receptor beta chain gene rearrangement analysis represents an accurate, objective, and sensitive molecular genetic marker of T cell lineage and clonality that allows discrimination among non-T cell, polyclonal T cell and monoclonal T cell populations. Non-T cells exhibit the TCR-beta gene germline configuration.(ABSTRACT TRUNCATED AT 400 WORDS)
authors.affiliation: Department of Pathology, College of Physicians and Surgeons of Columbia University, New York, New York 10032.
authors.forename: D M
authors.initials: DM
authors.lastname: Knowles
mesh_terms: D002454:Cell Differentiation; D002471:Cell Transformation, Neoplastic / Q000276:immunology; D015321:Gene Rearrangement; D015329:Gene Rearrangement, T-Lymphocyte; D005803:Genes, Immunoglobulin; D006801:Humans; D007147:Immunoglobulin Light Chains / Q000235:genetics; D015458:Leukemia, T-Cell / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D008223:Lymphoma / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D016403:Lymphoma, Large B-Cell, Diffuse / Q000235:genetics / Q000276:immunology / Q000473:pathology; D008228:Lymphoma, Non-Hodgkin / Q000235:genetics / Q000276:immunology / Q000473:pathology; D008232:Lymphoproliferative Disorders / Q000235:genetics / Q000276:immunology / Q000473:pathology; D010641:Phenotype; D012871:Skin Diseases / Q000235:genetics / Q000276:immunology / Q000473:pathology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology / Q000648:ultrastructure
chemical_list: D007147:Immunoglobulin Light Chains