A set of related cancers that form in the bone marrow and other blood-producing organs.

Leukemia is named after the leukocytes, white blood cells which mutate before maturity and become cancerous. These cells reproduce rapidly, suppressing production of normal white cells that are essential to fighting infection in the body, and red cells that are needed to carry oxygen in the blood. Cancer cells may spread to the liver, spleen, lymph nodes, genitals, or the brain.

After accidents, leukemia is the leading cause of death for children ages 2-15. It is the most common form of cancer among children, accounting for up to one-third of childhood cancers. Of 28,000 cases diagnosed per year, 2,500 are children. The incidence of leukemia peaks between the ages of 3-5 for whites, but remains constant up until age 20 for non-white populations. There are several types of leukemia, depending on the type of blood cell...