Encyclopedia of Cancer | Acute Lymphocytic Leukemia

Definition

Acute lymphocytic leukemia is a cancer of the white blood cells known as lymphocytes.

Description

Leukemia is a cancer of white blood cells. In acute leukemia, the cancerous cells are immature forms called blasts that cannot properly fight infection; patients become ill in rapid fashion.

The cells that make up blood are produced in the bone marrow and the lymph system. The bone marrow is the spongy tissue found in the large bones of the body. The lymph system includes the spleen (an organ in the upper abdomen), the thymus (a small organ beneath the breast-bone), and the tonsils (an organ in the throat). In addition, the lymph vessels (tiny tubes that branch like blood vessels into all...