Chromosome studies of hematopoietic colonies for distinct diagnosis of megakaryoblastic crisis of chronic myelogenous leukemia: A case report

Abstract Chromosome studies of cells from megakaryocytic colonies (CFU-Meg) as evidenced by a megakaryocyte-specific monoclonal antibody, TP80, from a patient with chronic myelogenous leukemia (CML) in the blast crisis (BC) revealed the same aberrant karyotype, 52,XY,+9, +9, +18, +19, +21, +22, t(9;22)(q34;q11),t(9;22), as that having newly appeared in the peripheral blood. Cells from erythroid bursts (BFU-E) showed only the standard 46,XY,t(9;22) karyotype, and cells from granulocyte/macrophage colonies (CFU-GM) had either of these karyotypes. These results demonstrated that the whole megakaryocytic line and part of the granulocyte/macrophage line had been involved in the BC while the erythroid line totally belonged to the original clone. Chromosome analysis coupled with immunophenotyping of hemopoietic colonies was useful for a definite diagnosis of megakaryoblastic crisis of CML in this patient.