title: Immunophenotypic and genotypic characteristics of chronic myelogenous leukemia in blast crisis.
abstract: BACKGROUND
  Chronic myelogenous leukemia (CML) may transform into blast crisis (BC) if not properly treated. Among patients with transformation, 20% to 30% will develop BC with lymphoid-associated antigens (Ly-BC), and the remaining cases with myeloid-associated antigens (My-BC) or with both (Mix-BC). In this study, we investigated the lineage of blast cells in CML-BC using immunophenotypic and genetic analyses and analyzed the prognostic significance of genotypic change in CML-BC.
  
  
  METHODS
  Twenty-one patients with CML-BC diagnosed at the Taipei Veterans General Hospital from 1982 to 1992 were included. Immunophenotyping was done by using the avidin-biotin immunoperoxidase technique. Genetic analyses were carried out by using Southern Blot hybridization. The prognostic influence of genotypic change was analyzed.
  
  
  RESULTS
  Thirteen patients (61.9%) expressed myeloid-associated antigens, one patient (4.8%) expressed megakaryoblast-associated antigens, four patients (19%) expressed B lymphoid-associated antigens and three patients (14.3%) expressed both myeloid and B lymphoid antigens. Clonal rearrangement of the immunoglobulin heavy chain (IgH) gene was found in six cases. Among them, four expressed B lymphoid markers only and two expressed both myeloid and B lymphoid markers. Patients with clonal IgH gene rearrangement tended to have a better response to chemotherapy (50% vs 8.3%, p = 0.08) and significantly longer survival (median survival, 5 months vs 3 months, p < 0.05) than did those with a germline configuration.
  
  
  CONCLUSIONS
  Clonal rearrangement of the IgH gene was found mostly in cases of Ly-BC and Mix-BC. We found that CML-BC with clonal rearrangement of the IgH gene had a more favorable prognosis than in cases with a germline configuration.
authors.affiliation: Section of Medical Oncology, Department of Medicine, Taipei Veterans General Hospital, National Yang-Ming University School of Medicine, Taipei, Taiwan, ROC.
authors.forename: C C
authors.initials: CC
authors.lastname: Yen
authors.forename: J H
authors.initials: JH
authors.lastname: Liu
authors.forename: W S
authors.initials: WS
authors.lastname: Wang
authors.forename: F S
authors.initials: FS
authors.lastname: Fan
authors.forename: T J
authors.initials: TJ
authors.lastname: Chiou
authors.forename: C J
authors.initials: CJ
authors.lastname: Tai
authors.forename: M H
authors.initials: MH
authors.lastname: Yang
authors.forename: T C
authors.initials: TC
authors.lastname: Chao
authors.forename: L T
authors.initials: LT
authors.lastname: Hsiao
authors.forename: P M
authors.initials: PM
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001752:Blast Crisis / Q000235:genetics / Q000276:immunology / Q000473:pathology*; D005260:Female; D005838:Genotype; D006801:Humans; D016130:Immunophenotyping; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D008297:Male; D008875:Middle Aged