What is leukemia?
Leukemia is a cancer that starts in the stem cells of the bone marrow that make blood cells. Bone marrow is the soft, spongy material that fills the centre of most bones (where blood cells are made). Blood stem cells (immature blood cells) develop into either myeloid stem cells or lymphoid stem cells.
Myeloid stem cells develop into one of three types of mature blood cells:
-
Red blood cells carry oxygen to all tissues of the body.
-
Platelets form clots in damaged blood vessels to prevent bleeding.
-
White blood cells called granulocytes and monocytes destroy bacteria and help to fight infection.
Lymphoid stem cells develop into lymphocytes. Lymphocytes are another type of white blood cell that is usually found in the lymph nodes and lymphatic system, such as the spleen and the blood. Lymphocytes make antibodies to help fight infection.
Leukemia develops when the blood stem cells in the bone marrow make abnormal blood cells. These abnormal cells are called leukemia cells. Over time, the leukemia cells crowd out normal blood cells. This makes it hard for the white blood cells, red blood cells and platelets to do their jobs.
Types of leukemia
Last modified on:
13 December 2009
Back to top