Chronic Myeloid Leukemia (Chronic Myeloid Leukemia) is often divided into three phases, based on clinical characteristics and laboratory findings. In the absence of interventions, Chronic Myeloid Leukemia typically begins in the chronic phase (85% of Chronic Myeloid Leukemia patients). Over the course of several years, the cancer progresses to an accelerated phase and ultimately to a blast crisis phase.