Chromosome 7 abnormalities in acute megakaryoblastic leukemia associated with Down syndrome.
A 2-year-old girl with Down syndrome (DS) developed acute megakaryoblastic leukemia (AMKL) following a transient myeloproliferative disorder (TMD). The blast cells showed an altered karyotype of 47,XX,r(7),+21c. Serial cytogenetic studies during the course of the illness showed rapid stepwise clonal chromosome changes, including a ring chromosome 7, associated with treatment refractoriness. We reviewed 10 published cases of Down syndrome-related AMKL (DS-AMKL) showing chromosome 7 abnormalities and found that these changes do not carry the same prognostic weight as for non-DS children. For DS-AMKL, therefore, other prognostic factors besides clonal cytogenetic changes need to be identified for planning optimal therapy.
Kobayashi
Ken-Ichiro
K
Department of Pediatrics, Kobe City General Hospital, 4-6 Minatojima-Nakamachi, Chuo-ku, Kobe 6500046, Japan. ckg-kobayashi@rio.odn.ne.jp <ckg-kobayashi@rio.odn.ne.jp>
Usami
Ikuya
I
Kubota
Masaru
M
Nishio
Toshikazu
T
Kakazu
Naoki
N
D002675:Child, Preschool; D002869:Chromosome Aberrations; D025063:Chromosome Disorders; D002897:Chromosomes, Human, Pair 7; D018450:Disease Progression; D004314:Down Syndrome / Q000150:complications / Q000235:genetics*; D005260:Female; D006801:Humans; D007947:Leukemia, Megakaryoblastic, Acute / Q000150:complications / Q000235:genetics*; D012303:Ring Chromosomes; D032681:Spectral Karyotyping; D014314:Trisomy