title: Lymphoid blast crisis of B-lineage phenotype with monosomy 7 in a patient with juvenile chronic myelogenous leukemia (JCML).
abstract: We studied a patient with juvenile chronic myelogenous leukemia (JCML) whose terminal course was characterized by transformation to acute lymphoblastic leukemia. Karyotypic studies identified monosomy 7 in leukemic myelomonocytic marrow cells during the chronic phase and in the lymphoblasts during the transformation phase. Our ability to sustain the transformed lymphoblasts in culture allowed us to characterize them further. CD19, HLA-DR, and CD10 were present, consistent with a pre-B acute lymphoblastic leukemia phenotype. CD14 (My-4) and CD13 (My-7) were negative. Rearrangement of immunoglobulin heavy- and light-chain genes identified monoclonal populations of cells of the B lineage. This case provides further evidence that JCML is a clonal disease of pluripotent stem-cell origin.
authors.affiliation: Division of Haematology/Oncology, Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: R C
authors.initials: RC
authors.lastname: Lau
authors.forename: J
authors.initials: J
authors.lastname: Squire
authors.forename: L
authors.initials: L
authors.lastname: Brisson
authors.forename: S
authors.initials: S
authors.lastname: Kamel-Reid
authors.forename: T
authors.initials: T
authors.lastname: Grunberger
authors.forename: I
authors.initials: I
authors.lastname: Dubé
authors.forename: M
authors.initials: M
authors.lastname: Letarte
authors.forename: K
authors.initials: K
authors.lastname: Shannon
authors.forename: M H
authors.initials: MH
authors.lastname: Freedman
mesh_terms: D001752:Blast Crisis / Q000235:genetics / Q000473:pathology*; D002897:Chromosomes, Human, Pair 7; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain; D015328:Gene Rearrangement, B-Lymphocyte, Light Chain; D006801:Humans; D016130:Immunophenotyping; D007223:Infant; D007621:Karyotyping; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics / Q000473:pathology*; D008297:Male; D009006:Monosomy; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics / Q000473:pathology*