Malignant myeloid transformation with isochromosome 7q in Shwachman-Diamond syndrome.
Shwachman-Diamond syndrome is an autosomal recessive disorder characterized by exocrine pancreatic dysfunction, bony metaphyseal dysostosis, various degrees of cytopenia, and a striking tendency to develop myelodysplastic syndrome and acute myeloblastic leukemia. Isochromosome 7 [i(7q)] is a rare non-random cytogenetic abnormality of myeloid cells in hematological malignancy. We report two cases of Shwachman-Diamond syndrome in which patients developed myelodysplastic syndrome and i(7q), detected by G-banding karyotype analysis and fluorescence in situ hybridization. Three other children have been previously reported to have myelodysplastic syndrome in association with i(7q); two of them had Shwachman-Diamond syndrome. Isochromosome 7q may be a fairly specific marker of myeloid malignant transformation in this syndrome and play a role in its pathogenesis.
Department of Paediatrics, The Hospital for Sick Children and University of Toronto, Ontario, Canada.
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Y
Dror
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Squire
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Durie
M H
MH
Freedman
D001854:Bone Marrow Cells / Q000473:pathology; D002471:Cell Transformation, Neoplastic; D002871:Chromosome Banding; D002897:Chromosomes, Human, Pair 7; D004413:Dysostoses / Q000235:genetics; D010188:Exocrine Pancreatic Insufficiency / Q000235:genetics; D005808:Genes, Recessive; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D018404:Isochromosomes; D007621:Karyotyping; D015470:Leukemia, Myeloid, Acute / Q000235:genetics* / Q000473:pathology; D008297:Male; D009190:Myelodysplastic Syndromes / Q000235:genetics* / Q000473:pathology; D013577:Syndrome