Illustration of cancerous myeloblasts (purple), a form of white blood cell precursor, resulting from acute myeloid leukaemia (AML). Healthy red blood cells (red discs) and white blood cells (purple) are visible in the surrounding blood. AML is a cancer affecting the bone marrow (myeloid tissue) causing the overproduction of myeloblasts. The excess cells can stop other blood cells from developing correctly, and can enter the bloodstream spreading to other parts of the body. The acute form can develop quickly and can be fatal in a matter of weeks if left untreated. Treatment can involve immunotherapy, chemotherapy and radiotherapy.