Myeloid leukemia is a form of cancer where the bone marrow makes too many myeloid cells (granulocytes and their precursors) in the bone marrow which accumulates in the blood and eventually invades various parts of the body. The aggressive phase of myeloid leukemia follows the chronic form and is a sign that the condition is progressing more rapidly to a blast crisis which is the final stage of leukemia. See also Leukemia, Myeloid, Aggressive-Phase