Definition

Leukemia (pronounced loo-KEE-mee-uh) is a form of cancer (see cancer entry) in which the body produces too many white blood cells. Many forms of leukemia have been identified. They are divided into two general types: acute and chronic. An acute condition comes on fairly quickly. A chronic disorder develops more slowly over time.

Description

Blood contains three types of cells: red blood cells, white blood cells, and platelets (pronounced PLATE-lits). Each type of cell has a special function in the body. Red blood cells carry oxygen from the lungs to the rest of the body. White blood cells fight invading organisms, such as bacteria and viruses. Platelets are involved in the process of blood clotting.

All blood cells form in the soft tissue that fills the center of bones. This tissue is called bone marrow. All three types of blood cells arise out of a primitive type...