Acute Lymphocytic Leukemia

Leukemia is a cancer of the blood-forming cells that affects both adults and children. Leukemia is the most common form of cancer diagnosed in children and adolescents, and often arises very rapidly over a short period of time (acute form). In adults, leukemia is more likely to take many years to develop (chronic form) and accounts for about 3% of all cancer diagnosed annually. Leukemias are further grouped according to the type of blood cell affected, with major subtypes including lymphocytic and myeloid types. The major childhood leukemias include acute lymphocytic and acute myeloid leukemia, whereas in adults, major subtypes include chronic lymphocytic leukemia and acute myeloid leukemia. The causes of leukemia are not well understood, but appear to involve a combination of hereditary and environmental factors.