title: Heterogeneity of acute myeloblastic leukemia without maturation: an ultrastructural study.
abstract: We demonstrated by ultrastructural examination that the leukemic blasts of 13 patients with acute myeloblastic leukemia (AML) without maturation (M1 in the French-American-British classification) showed heterogeneous features. In 7 patients, the leukemic blasts had a high level of light microscopic myeloperoxidase positivity (> 50%). Ultrastructurally, the cells were myeloblast-promyelocytes with 100% myeloperoxidase positivity, and these 7 patients appeared to have typical AML. In contrast, the remaining 6 patients had leukemic blasts with a low myeloperoxidase positivity (< 50%) and heterogeneous features. Three had ultrastructural features of myelomonocytic or monocytic lineage, 1 had myelomonocytic cells associated with megakaryoblasts, and 1 had undifferentiated blasts. The former group had a better prognosis than the latter, indicating that ultrastructural analysis of M1 leukemia may help predict the response to therapy.
authors.affiliation: First Department of Internal Medicine, Kansai Medical University, Osaka, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Hamamoto
authors.forename: M
authors.initials: M
authors.lastname: Date
authors.forename: H
authors.initials: H
authors.lastname: Taniguchi
authors.forename: T
authors.initials: T
authors.lastname: Nagano
authors.forename: Y
authors.initials: Y
authors.lastname: Kishimoto
authors.forename: T
authors.initials: T
authors.lastname: Kimura
authors.forename: S
authors.initials: S
authors.lastname: Fukuhara
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001853:Bone Marrow / Q000201:enzymology / Q000276:immunology / Q000648:ultrastructure*; D002467:Cell Nucleus / Q000648:ultrastructure; D003561:Cytarabine / Q000008:administration & dosage / Q000031:analogs & derivatives; D003593:Cytoplasm / Q000648:ultrastructure; D003630:Daunorubicin / Q000008:administration & dosage; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D015470:Leukemia, Myeloid, Acute / Q000188:drug therapy / Q000201:enzymology / Q000473:pathology*; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D015388:Organelles / Q000648:ultrastructure; D009195:Peroxidase / Q000032:analysis; D011379:Prognosis
chemical_list: D003561:Cytarabine; C015019:enocitabine; D009195:Peroxidase; D003630:Daunorubicin