Myelodysplastic syndrome in a child with constitutional trisomy 8 mosaicism and normal phenotype.
Trisomy 8 is a frequently acquired cytogenetic abnormality in myeloid malignancies, but may also represent a constitutional chromosome abnormality with a wide phenotypic variation. We report a case of myelodysplastic syndrome (MDS) that developed in a child with trisomy 8 mosaicism and normal phenotype. Bone marrow (BM) cells all showed trisomy 8 with additional clonal abnormalities in most cells. Based on the present case and a review of previously published cases of myeloid malignancies in patients with trisomy 8 mosaicism, it appears likely that the malignant cells developed from the trisomic cell population, suggesting that constitutional trisomy 8 may be a predisposing condition to myeloid malignancies. Trisomy 8 in malignant cells is usually considered an acquired abnormality, but this implies a risk of ignoring a constitutional trisomy 8 mosaicism. Examination for constitutional trisomy 8, despite a normal phenotype, may therefore be warranted in hematologic malignancies with trisomy 8 of BM cells to evaluate further the possible association and to preclude erroneous use of trisomy 8 as a tumor marker.
Department of Pediatrics, Odense University Hospital, Denmark.
H
H
Hasle
N
N
Clausen
B
B
Pedersen
K
K
Bendix-Hansen
D002648:Child; D002898:Chromosomes, Human, Pair 8; D006801:Humans; D007621:Karyotyping; D008297:Male; D009030:Mosaicism; D009190:Myelodysplastic Syndromes / Q000235:genetics*; D010641:Phenotype; D014314:Trisomy / Q000235:genetics*