Prognostic impact of trisomies of chromosomes 10, 17, and 5 among childrenwith acute lymphoblastic leukemia and high hyperdiploidy (> 50 chromosomes)

Purpose: Children with acute lymphoblastic leukemia (ALL) and high hyperdip loidy (> 50 chromosomes) have improved outcome compared with other ALL pati ents. We sought to identify cytogenetic features that would predict differe nces in outcome within this low-risk subset of ALL patients. Materials and Methods: High-hyperdiploid ALL patients (N = 480) were enroll ed between 1988 and 1995 on Children's Cancer Group (CCG) trials. Karyotype s were determined by conventional banding. Treatment outcome was analyzed b y life-table methods. Results: Patients with 54 to 58 chromosomes had better outcome than patient s with 51 to 53 or 59 to 68 chromosomes (P = .0002). Patients with a trisom y of chromosome 10 (P < .0001), chromosome 17 (P = .0002), or chromosome 18 (P = .004) had significantly improved outcome compared with their counterp arts who lacked the given trisomy. Patients with a trisomy of chromosome 5 had worse outcome than patients lacking this trisomy (P = .02). Patients wi th trisomies of both chromosomes 10 and 17 had better outcome than those wi th ct trisomy of chromosome 10 (P = .09), a trisomy of chromosome 17 (P = . 01), or neither trisomy (P < .0001). Multivariate analysis indicated that t risomy of chromosome 10 (P = .001) was the most significant prognostic fact or for high-hyperdiploid patients, yet trisomy of chromosome 17 (P =.02) or chromosome 5 (P = .01) and modal chromosome number (P = .02) also had sign ificant multivariate effects. Conclusion: Trisomy of chromosomes 10 and 17 as well as modal chromosome nu mber 54 to 58 identify subgroups of patients with high-hyperdiploid ALL who have a better outcome than high-hyperdiploid patients who lack these cytog enetic features. Trisomy of chromosome 5 confers poorer outcome among high- hyperdiploid patients. (C) 2000 by American Society of Clinical Oncology.