Promyelocytic blast crisis of chronic myelocytic leukemia with both t(9;22) and t(15;17) in M3 cells.
A blast crisis with the features of promyelocytic leukemia (M3) occurred during the evolution of chronic myelocytic leukemia (CML) with the t(9;22) translocation. This rare form of transformation was confirmed by means of cytologic and electron microscopic examination. Cytogenetic studies showed two simultaneous translocations t(15;17) and t(9;22) in the promyelocytes. After intensive chemotherapy, a complete remission was obtained and only karyotypes with t(9;22) translocation were present. These data confirm the specificity of the t(15;17) translocation in malignant promyelocytic proliferation and provide evidence for a second genetic event in the genesis of blast crisis occurring in a committed cell belonging to the abnormal population defined by the Ph1 chromosome.
D001853:Bone Marrow / Q000473:pathology; D002901:Chromosomes, Human, 13-15; D002902:Chromosomes, Human, 16-18; D002904:Chromosomes, Human, 21-22 and Y; D002906:Chromosomes, Human, 6-12 and X; D006801:Humans; D007621:Karyotyping; D007951:Leukemia, Myeloid / Q000235:genetics* / Q000473:pathology; D015470:Leukemia, Myeloid, Acute / Q000235:genetics* / Q000473:pathology; D008854:Microscopy, Electron; D014178:Translocation, Genetic