Isochromosomes in childhood acute lymphoblastic leukemia: A collaborative study of 83 cases

Academic Article

Abstract

  • Cytogenetic analysis of leukemic cells from 2,805 children with newly diagnosed acute lymphoblastic leukemia (ALL) identified 83 cases (3%) that had a stemline with at least one isochromosome. The i(9q) was present in 28 (1%), the i(17q) in 23 (0.8%), and the i(7q) in 23 (0.8%). Other isochromosomes-i(21q), i(6p), i(1q), i(8q), or i(Xq)-were found in only 12 cases (0.4%). The isochromosome cases were more likely than were other ALL cases to have a pre-B immunophenotype (38% v 25%, P = .02) and leukemic cell hyperdiploidy >50 (37% v 24%, P = .02); five cases had both features. The i(9q) was associated with age greater than 10 years (P < .05) and the pre-B immunophenotype (P = .05); both the i(17q) and i(7q) had high frequencies of hyperdiploidy >50 (P < .0001 and P = .05, respectively). The t(1;19)(q23;p13) was a common feature (23%) in cases with the i(9q), i(7q), i(6p), or i(1q). These findings establish the i(9q), i(17q), and i(7q) as nonrandom chromosomal abnormalities in ALL. The prognostic significance of the presence of isochromosome(s) remains to be determined.
  • Pubmed Id

  • 15537888
  • Author List

  • Pui CH; Carroll AJ; Raimondi SC; Schell MJ; Head DR; Shuster JJ; Crist WM; Borowitz MJ; Link MP; Behm FG
  • Start Page

  • 2384
  • End Page

  • 2391
  • Volume

  • 79
  • Issue

  • 9