title: Incidence and relevance of secondary chromosome abnormalities in childhood TEL/AML1+ acute lymphoblastic leukemia: an interphase FISH analysis.
abstract: The aim of the present study was to determine the frequency and clinical relevance of the most common secondary karyotype abnormalities in TEL/AML1+ B-cell precursor acute lymphoblastic leukemia (ALL) as assessed with fluorescence in situ hybridization (FISH) analyses. Screening of 372 patients who were enrolled in two consecutive Austrian childhood ALL multicenter trials identified 94 (25%) TEL/AML1+ cases. TEL deletions, trisomy 21 and an additional der(21)t(12;21) were detected in 52 (55%), 13 (14%) and 14 (15%) TEL/AML1+ patients, respectively. The 12p aberrations (P=0.001) and near tetraploidy (P=0.045) were more common in TEL/AML1+ patients, whereas the incidence of diploidy, pseudodiploidy, hypodiploidy, low hyperdiploidy, near triploidy, del(6q), chromosome 9 and 11q23 abnormalities was similar among TEL/AML1+ and TEL/AML1- patients. None of the TEL/AML1+ patients had a high hyperdiploid karyotype. Univariate analysis indicated that among TEL/AML1+ patients those with a deletion of the nontranslocated TEL allele had a worse prognosis than those without this abnormality (P=0.034). We concluded that the type and incidence of the most common secondary aberrations in TEL/AML1+ ALL can be conveniently identified with little additional effort during interphase screening with appropriate TEL and AML1 FISH probes. We also provided preliminary evidence that the deletion of the nontranslocated TEL allele may adversely influence the clinical course of TEL/AML1+ ALL.
authors.affiliation: 1St Anna Children's Hospital, Vienna, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Attarbaschi
authors.forename: G
authors.initials: G
authors.lastname: Mann
authors.forename: M
authors.initials: M
authors.lastname: König
authors.forename: M N
authors.initials: MN
authors.lastname: Dworzak
authors.forename: M M
authors.initials: MM
authors.lastname: Trebo
authors.forename: N
authors.initials: N
authors.lastname: Mühlegger
authors.forename: H
authors.initials: H
authors.lastname: Gadner
authors.forename: O A
authors.initials: OA
authors.lastname: Haas
mesh_terms: D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations; D002881:Chromosomes, Human, Pair 12 / Q000235:genetics; D002891:Chromosomes, Human, Pair 21 / Q000235:genetics; D050676:Core Binding Factor Alpha 2 Subunit; D004314:Down Syndrome; D005260:Female; D017353:Gene Deletion; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D015994:Incidence; D007223:Infant; D007399:Interphase / Q000235:genetics*; D007621:Karyotyping; D008297:Male; D015514:Oncogene Proteins, Fusion / Q000235:genetics / Q000378:metabolism*; D011003:Ploidies; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics*; D012189:Retrospective Studies; D014178:Translocation, Genetic; D000097764:ETS Translocation Variant 6 Protein
chemical_list: D050676:Core Binding Factor Alpha 2 Subunit; D015514:Oncogene Proteins, Fusion; C102421:TEL-AML1 fusion protein; D000097764:ETS Translocation Variant 6 Protein