title: [Prognostic impact of loss of sex chromosomes in children with acute myeloid leukemia subtype M2].
abstract: OBJECTIVE
  To study the relationship between loss of sex chromosomes and prognosis in children with acute myeloid leukemia (AML) M2 subtype.
  
  
  METHODS
  According to cytogenetic characteristics, 106 children with AML were divided into three groups: patients with normal karyotype (Group A, n=26), patients with abnormal karyotype who had no loss of sex chromosomes (Group B, n=52), and patients with abnormal karyotype who had loss of sex chromosomes (Group C, n=28). Prognosis was compared between the three groups.
  
  
  RESULTS
  The 5-year event-free survival (EFS) rates of Groups A, B, and C were (38.9±11.2)%, (59.3±7.3)%, and (66.5±10.5)%, respectively; the EFS of Group C was significantly higher than that of Group A (P=0.035). The 5-year overall survival (OS) rates of Groups A, B, and C were (54.3±13.5)%, (68.1±7.7)%, and (77.9±9.8)%, respectively (P>0.05). The 5-year EFS of 58 patients with t(8;21) was (63.3±7.3)%, significantly higher than that of patients with normal karyotype (P=0.015). All the 28 cases in Group C had t(8;21), and their 5-year EFS was not significantly different from that of patients with t(8;21) in Group B (P>0.05).
  
  
  CONCLUSIONS
  Loss of sex chromosomes is a favorable karyotype in children with AML M2 subtype and the patients in this group mostly have t(8;21). Why loss of sex chromosomes indicates a favorable prognosis is probably because it is accompanied by t(8;21) in the patients.
authors.affiliation: Department of Pediatrics, Peking University People's Hospital, Beijing 100044, China. zuoyingxi@pkuph.edu.cn.
authors.forename: Yue-Ping
authors.initials: YP
authors.lastname: Jia
authors.forename: Ying-Xi
authors.initials: YX
authors.lastname: Zuo
authors.forename: Ai-Dong
authors.initials: AD
authors.lastname: Lu
authors.forename: Le-Ping
authors.initials: LP
authors.lastname: Zhang
authors.forename: Gui-Lan
authors.initials: GL
authors.lastname: Liu
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002891:Chromosomes, Human, Pair 21; D002898:Chromosomes, Human, Pair 8; D005260:Female; D006801:Humans; D059785:Karyotype; D015470:Leukemia, Myeloid, Acute / Q000235:genetics* / Q000401:mortality; D008297:Male; D011379:Prognosis; D012729:Sex Chromosome Aberrations; D014178:Translocation, Genetic