What are the phases of chronic myelogenous leukemia?

After a diagnosis of CML-doctors assign a phase that indicates how far the disease has progressed and what treatment options are available. The phases are descriptive and divided up into three categories based on the percentage of the blood containing cancerous cells: chronic-accelerated-and blastic. Chronic phase consists of 10 percent or fewer cancer cells in the blood-and is very favorable in its response to treatment. Accelerated phase is when 10 to 19 percent of cells in the blood are cancerous-and sees the symptoms becoming more pronounced and aggressive. Blastic-the final phase-occurs once the count of cancer cells in the blood exceeds 20 percent. This is the most serious and deadliest phase of the disease-and is when blast crisis can occur.