title: CD56+CD7+ stem cell leukemia/lymphoma with D2-Jdelta1 rearrangement.
abstract: OBJECTIVE
  We describe the characteristics of three patients with CD56+CD7+ stem cell leukemia/lymphoma.
  
  
  METHODS
  These blasts were analyzed for morphologic, karyotypic, immunophenotypic, and immunogenotypic features using Southern blot and polymerase chain reaction analysis.
  
  
  METHODS
  Peripheral blood, bone marrow aspirates, or biopsied mediastinal tumor specimens of three CD56+CD7+ stem cell leukemia/lymphoma patients were investigated.
  
  
  RESULTS
  The bone marrow of all patients showed myeloperoxidase (MPO) negative blast cells with basophilic cytoplasm and distinct nucleoli with no azurophilic granules. The blasts of two patients were classified as acute lymphoblastic leukemia (L2). The liver, spleen, and lymph nodes were unaffected in all patients. All had an aggressive clinical course. The blasts were strongly positive for both CD7 and CD56 but negative for other T-lineage associated antigens, including CD1, CD2, surface membrane CD3, cytoplasmic CD3c (2/2), CD4, CD5 and CD8. The additional antigens were recognized as follows: CD19 (1/3 cases) as a B lineage, CD33 (1/3) as a myeloid marker, CD34 (2/3) as a stem cell, CD38 (1/1) and HLA-DR (2/3). When the patients relapsed, the phenotypes changed to blasts positive for CD5, CD10 and CD13 in patient 1, CD5 in patient 2, and CD33 in patient 3. MPO, however, remained negative. Cytogenetic analysis showed no common abnormal karyotype. All had a common D2-Jdelta1 induced by T-cell specific enhancer. Rearrangement of TCR beta and gamma genes occurred in patient 2, and IgH and TCR beta underwent rearrangement in patient 3.
  
  
  CONCLUSIONS
  Although a more comprehensive case analysis is necessary, these data suggest the possibility that the blasts of the present cases come from a common lymphoid precursor (T, NK, and B cell) or from a NKT precursor as the fourth lymphoid lineage.
authors.affiliation: First Department of Internal Medicine, Fukuoka University School of Medicine.
authors.forename: T
authors.initials: T
authors.lastname: Yoshida
authors.forename: N
authors.initials: N
authors.lastname: Kimura
authors.forename: H
authors.initials: H
authors.lastname: Sawada
authors.forename: E
authors.initials: E
authors.lastname: Suematsu
authors.forename: M
authors.initials: M
authors.lastname: Nagano
authors.forename: T
authors.initials: T
authors.lastname: Akiyoshi
authors.forename: S
authors.initials: S
authors.lastname: Motomura
authors.forename: M
authors.initials: M
authors.lastname: Kikuchi
authors.forename: J
authors.initials: J
authors.lastname: Nishimura
authors.forename: K
authors.initials: K
authors.lastname: Tamura
mesh_terms: D000208:Acute Disease; D000328:Adult; D019011:Antigens, CD7 / Q000378:metabolism*; D001402:B-Lymphocytes / Q000276:immunology / Q000473:pathology; D001483:Base Sequence; D019002:CD56 Antigen / Q000378:metabolism*; D003582:Cytogenetics; D017931:DNA Primers / Q000235:genetics; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain; D015333:Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; D016694:Gene Rearrangement, delta-Chain T-Cell Antigen Receptor; D015334:Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor; D005838:Genotype; D006801:Humans; D016130:Immunophenotyping; D007694:Killer Cells, Natural / Q000276:immunology / Q000473:pathology; D007938:Leukemia / Q000235:genetics* / Q000276:immunology* / Q000473:pathology; D008223:Lymphoma / Q000235:genetics* / Q000276:immunology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D014411:Neoplastic Stem Cells / Q000276:immunology* / Q000473:pathology; D013601:T-Lymphocytes / Q000276:immunology / Q000473:pathology
chemical_list: D019011:Antigens, CD7; D019002:CD56 Antigen; D017931:DNA Primers