title: Cytogenetic, cytomorphologic, and immunologic analysis in 55 children with acute lymphoblastic leukemia.
abstract: This paper presents the results of cytogenetic analysis in 55 children with acute lymphatic leukemia (ALL). Acquired chromosome aberrations were identified in 35 (63.6%) children. Difference in frequency of clonal aberrations depending on age of patients was observed. Thus, acquired aberrations were detected in all three children up to 6 months of age, in 57.8% in the group from 1-10 years, and in six (85.7%) of seven children older than 10 years of age at diagnosis. The analysis revealed chromosome aberrations specific for ALL. Hyperdiploidy >50 was identified in 20% of children, and the association with CALLA+ early pre-B and L2-ALL was observed. del(6) and t(1;19) were identified in 7.3% and 5.5% of children, respectively. No association with a specific morphology or specific immunophenotype for both structural aberrations has been established. The association of structural aberrations involving regions 14q11-12 and T-cell ALL, however, has been observed, as an aberration was identified in two (3.6%) children, i.e., in 25% of our T-cell leukemias. Interstitial deletion of the long arm of chromosome 13, a rare chromosomal aberration in ALL, was identified in addition to del(9)(q31) in a 17-month-old girl with constitutional trisomy of chromosome 21 and B-cell ALL-L2. Interesting is the finding of hyperdiploidy with 52 chromosomes and structural aberrations of chromosome 1 in a 1-month-old girl with morphologically unclassified CALLA+ pre-T acute leukemia. To our knowledge this is the first case of hyperdiploidy >50 in a neonatal leukemia.
authors.affiliation: Cytogenetic Laboratory, Children's Hospital, Zagreb, Croatia.
authors.forename: I
authors.initials: I
authors.lastname: Petković
authors.forename: K
authors.initials: K
authors.lastname: Josip
authors.forename: M
authors.initials: M
authors.lastname: Nakić
authors.forename: M
authors.initials: M
authors.lastname: Kastelan
mesh_terms: D000293:Adolescent; D001402:B-Lymphocytes / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations; D002872:Chromosome Deletion; D002878:Chromosomes, Human, Pair 1; D002883:Chromosomes, Human, Pair 14; D002888:Chromosomes, Human, Pair 19; D002896:Chromosomes, Human, Pair 6; D004171:Diploidy; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D007223:Infant; D007621:Karyotyping; D008297:Male; D015260:Neprilysin / Q000032:analysis; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics* / Q000276:immunology / Q000473:pathology; D013601:T-Lymphocytes / Q000276:immunology; D014178:Translocation, Genetic
chemical_list: D015260:Neprilysin