title: Adult B-cell acute lymphoblastic leukemia with two unrelated abnormal cytogenetic clones.
abstract: The presence of two different abnormal cell lines at diagnosis in hematologic malignancies is rare and raises the question of etiology and pathogenesis--two separate malignant lineages occurring together or a common stem cell malignancy? We present a 64-year-old woman who was evaluated for low platelet count and peripheral blasts. On the basis of the morphology, flow cytometry, and lack of myeloid-associated markers, a diagnosis of precursor B-cell acute lymphoblastic leukemia (B-ALL) was made. Cytogenetic analysis of the diagnostic bone marrow (BM) specimen revealed two unrelated abnormal clones--one had a dicentric (7;9)(p11;p11), resulting in the deletion of 7p and 9p, and the other had only trisomy 8. The dic(7;9) is a rare but recurrent abnormality in B-ALL, while trisomy 8 as a sole abnormality is most commonly associated with myeloid malignancies. After standard treatment for B-ALL, BM cytogenetic analysis showed disappearance of the dic(7;9) cell line but persistence of cells with trisomy 8. The presence of two unrelated clones suggestive of concomitant malignancies, possibly B-ALL with an underlying MDS, may have arisen by different mechanisms.
authors.affiliation: Department of Cytogenetics, Children's Hospital at Westmead, Westmead, NSW 2145, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Prabhu
authors.forename: D J
authors.initials: DJ
authors.lastname: Gottlieb
authors.forename: W
authors.initials: W
authors.lastname: Varikatt
authors.forename: L
authors.initials: L
authors.lastname: St Heaps
authors.forename: S
authors.initials: S
authors.lastname: Diaz
authors.forename: A
authors.initials: A
authors.lastname: Smith
mesh_terms: D000368:Aged; D002871:Chromosome Banding; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D015448:Leukemia, B-Cell / Q000235:genetics* / Q000473:pathology