Chronic lymphocytic leukemia
Chronic lymphocytic leukemia is a type of cancer in which the bone marrow makes too many lymphocytes (a type of white blood cell). Chronic lymphocytic leukemia (also called CLL) is a disease of the blood and bone marrow that usually gets worse slowly. It is the second most common type of leukemia in adults. Often occurs during or after middle age, is unusual in children. Advanced age influences the risk of chronic lymphocytic leukemia. Possible signs of chronic lymphocytic leukemia include swollen lymph nodes and fatigue.
Normally the body produces stem cells from bone marrow (immature cells) that become mature blood cells. There are 3 types of mature blood cells:
- Red blood cells that carry oxygen and other materials to all tissues.
- White blood cells that fight infection and disease.
- Platelets help prevent bleeding by forming blood clots.
In CLL, too high a number of stem cells becomes a type of white blood cell called lymphocytes. There are 3 types of lymphocytes:
- B lymphocytes that produce antibodies to help fight infection.
- T lymphocytes that help B lymphocytes make antibodies to fight infection.
- Natural killer cells that attack cancer cells or virus.
The lymphocytes in CLL infections do not control very well. Also, with increasing numbers of lymphocytes in the blood and bone marrow, decreases instead for white blood cells, platelets and red blood cells healthy. This can result in infection, anemia, easy bleeding.