leukemia, chronic myeloid

leukemia, chronic myeloid A malignant disease involving the white blood cells belonging to the myeloid line that is due to a chromosome rearrangement called the Philadelphia (or Ph) chromosome translocation. Abbreviated CML. CML has several phases that succeed one another. In the first phase, the chronic phase, there are few blast cells in blood and bone marrow and there may be no symptoms. This phase may last from several months to several years. In the next phase, the accelerated phase, there are more blast cells in blood and bone marrow and fewer normal cells. In the final phase, the blastic phase (or blast crisis), more than 30 percent of the cells in the blood or bone marrow are blast cells. Treatments may involve chemotherapy and bone marrow transplantation. Also called chronic myelocytic leukemia and chronic granulocytic leukemia.