Megakaryocytic blast crisis in a chronic myeloid leukemia patient with a rare variant of Philadelphia rearrangement t(9;22;22) and a constitutional translocation t(3;7).
Megakaryocytic blast crisis occurs extremely rarely, accounting for <3% of cases of chronic myelogenous leukemia in blastic transformation. In chronic myeloid leukemia, a variant Philadelphia translocation is reported in 2-10% of cases. We report an unusual case of megakaryocytic blast crisis with the Philadelphia variant rearrangement t(9;22;22) and a constitutional translocation t(3;7). The breakpoint in the 22q13 region was involved in this translocation. The chromosome region 22q13 harbors MKL1 gene, which is engaged in a specific translocation associated with acute megakaryoblastic leukemia. Study of deregulation of these four genes could contribute to better understanding of the effects of the t(9;22;22) rearrangement in a megakaryocytic blast crisis.
Jarmuz
Małgorzata
M
Department of Hematology, University of Medical Sciences, Poznan, Poland. maljar@man.poznan.pl <maljar@man.poznan.pl>
Kroll
Renata
R
Przybyłowicz-Chalecka
Anna
A
Ratajczak
Błazej
B
Gniot
Michał
M
Szyfter
Krzysztof
K
Komarnicki
Mieczysław
M
D000368:Aged; D001752:Blast Crisis / Q000235:genetics* / Q000473:pathology*; D002871:Chromosome Banding; D002892:Chromosomes, Human, Pair 22 / Q000235:genetics; D002893:Chromosomes, Human, Pair 3 / Q000235:genetics; D002897:Chromosomes, Human, Pair 7 / Q000235:genetics; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics* / Q000473:pathology*; D008533:Megakaryocytes / Q000473:pathology*; D010677:Philadelphia Chromosome