t(8;21)(q22;q22) in blast phase of chronic myelogenous leukemia.
The blast phase of chronic myelogenous leukemia (CML) frequently is associated with cytogenetic evidence of clonal evolution, defined as chromosomal aberrations in addition to the t(9;22)(q34;q11.2). We identified the t(8;21)(q22;q22) and other cytogenetic abnormalities by conventional cytogenetics and fluorescence in situ hybridization in 2 patients with t(9;22)-positive CML at the time of blast phase. The t(8;21), which typically is associated with a distinct subtype of de novo acute myeloid leukemia (AML) carrying the aml1/eto fusion gene, was accompanied by increased bone marrow myeloblasts (33%) in case 1 and extramedullary myeloid sarcoma in case 2, suggesting its possible role in disease progression. In case 1, the leukemic cells in aspirate smears had salmon-colored cytoplasmic granules, and immunophenotypic studies showed that the blasts expressed CD19. These findings suggest that the pathologic features of blast phase CML with the t(8;21) resemble those of de novo AML with the t(8;21).
Yin
C Cameron
CC
Department of Hematopathology, The University of Texas M.D. Anderson Cancer Center, Houston 77030, USA.
Medeiros
L Jeffrey
LJ
Glassman
Armand B
AB
Lin
Pei
P
D001752:Blast Crisis / Q000235:genetics*; D001853:Bone Marrow / Q000378:metabolism / Q000473:pathology*; D002891:Chromosomes, Human, Pair 21; D002898:Chromosomes, Human, Pair 8; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014178:Translocation, Genetic