title: Ploidy and clinical characteristics of childhood acute myeloid leukemia: A NOPHO-AML study.
abstract: We report the first large series (n = 596) of pediatric acute myeloid leukemia (AML) focusing on modal numbers (MN) from the population-based NOPHO-AML trials. Abnormal karyotypes were present in 452 cases (76%) and numerical aberrations were present in 40% (n = 237) of all pediatric AML. Among patients with an abnormal karyotype, the MN 46 was most common (n = 251; 56%) of which 36 (8%) were pseudodiploid with numerical aberrations, followed by MN 47 (n = 80; 18%) and MN 43-45 (n = 48; 8%). No cases had MN less than 43. Hyperdiploid AML with MN 48-65 comprised 11% of all cases and was associated with early onset (median age 2 years), female sex (57%), and a dominance of acute megakaryoblastic leukemia (AMKL) (29%). Hypodiploidy constituted 8% of all AML and was associated with older age (median age 9 years), male predominance (60%), FAB M2 (56%), and t(8;21)(q22;q22) (56%) with loss of sex chromosomes. Inferior outcome was observed for hypodiploid cases (5-year event-free survival 40% and 5-year overall survival 40%) but did not reach statistical significance. Chromosomes were gained in a nonrandom pattern, where chromosomes 8, 21, 19, and 6 were the most commonly gained. In conclusion, based on MNs, two cytogenetic subgroups with characteristic clinical features are described; hypodiploidy found in 8% and associated with high median age, male sex, t(8;21)(q22;q22), and FAB M2 and possibly associated with inferior outcome (P = 0.13), and hyperdiploidy with MN 48-65 in 11% associated with early onset, female sex, and AMKL.
authors.affiliation: Department of Pediatrics, Aarhus University Hospital, Skejby, Aarhus, Denmark.
authors.forename: Julie Damgaard
authors.initials: JD
authors.lastname: Sandahl
authors.forename: Eigil
authors.initials: E
authors.lastname: Kjeldsen
authors.forename: Jonas
authors.initials: J
authors.lastname: Abrahamsson
authors.forename: Shau-Yin
authors.initials: SY
authors.lastname: Ha
authors.forename: Jesper
authors.initials: J
authors.lastname: Heldrup
authors.forename: Kirsi
authors.initials: K
authors.lastname: Jahnukainen
authors.forename: Olafur G
authors.initials: OG
authors.lastname: Jónsson
authors.forename: Birgitte
authors.initials: B
authors.lastname: Lausen
authors.forename: Josefine
authors.initials: J
authors.lastname: Palle
authors.forename: Bernward
authors.initials: B
authors.lastname: Zeller
authors.forename: Erik
authors.initials: E
authors.lastname: Forestier
authors.forename: Henrik
authors.initials: H
authors.lastname: Hasle
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D015470:Leukemia, Myeloid, Acute / Q000235:genetics* / Q000473:pathology*; D008297:Male; D011003:Ploidies; D012189:Retrospective Studies