title: Acute megakaryoblastic leukemia in children and adolescents: a retrospective analysis of 24 cases.
abstract: In order to characterize the clinical, cytogenetic, and outcome features of childhood acute megakaryoblastic leukemia (AMKL), we reviewed 24 cases; 14 were identified among 150 consecutive newly diagnosed acute myelogenous leukemia (AML) patients at St. Jude Children's Research Hospital, and 10 were cases referred to the National Institute of Cancer in Rio de Janeiro, Brazil. There were 5 Down syndrome patients and one patient with chronic myeloid leukemia (Ph+) in blastic crisis. Twelve patients had significant hepatosplenomegaly. Leukemic cell morphology and cytochemistry were consistent with the M7 classification in 17 cases, and all cases tested expressed megakaryocytic surface antigens. AMKL patients were significantly younger than other AML patients (P = 0.0001) and had poorer responses to therapy (P = 0.03, univariate analysis only). Ten of 24 failed induction, and only 5 are disease-free at 6 months to 4.5+ years. We conclude that AMKL usually affects young children, frequently producing marked organomegaly. It comprises approximately 10% of pediatric AML cases, and responds poorly to intensive AML therapies.
authors.affiliation: Department of Hematology-Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105.
authors.forename: R C
authors.initials: RC
authors.lastname: Ribeiro
authors.forename: M S
authors.initials: MS
authors.lastname: Oliveira
authors.forename: D
authors.initials: D
authors.lastname: Fairclough
authors.forename: C
authors.initials: C
authors.lastname: Hurwitz
authors.forename: J
authors.initials: J
authors.lastname: Mirro
authors.forename: F G
authors.initials: FG
authors.lastname: Behm
authors.forename: D
authors.initials: D
authors.lastname: Head
authors.forename: M L
authors.initials: ML
authors.lastname: Silva
authors.forename: S C
authors.initials: SC
authors.lastname: Raimondi
authors.forename: W M
authors.initials: WM
authors.lastname: Crist
mesh_terms: D000293:Adolescent; D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001853:Bone Marrow / Q000473:pathology; D016026:Bone Marrow Transplantation; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations; D004314:Down Syndrome / Q000150:complications; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D007223:Infant; D007947:Leukemia, Megakaryoblastic, Acute / Q000097:blood / Q000188:drug therapy / Q000453:epidemiology* / Q000235:genetics / Q000473:pathology; D015993:Life Tables; D008297:Male; D014411:Neoplastic Stem Cells / Q000648:ultrastructure; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome