CLL (chronic lymphocytic leukemia) is a cancer of the blood and lymphatic systems.
The Lymphatic system contains Lymphocytes, which are a type of white blood cell. Together with other cells of the immune system, they work to fight infection and prevent disease.
CLL occurs when there is damage to the genes of developing lymphocytes in the bone marrow, which changes the lymphocytes so that they do not die as they are supposed to. These abnormal lymphocytes do not fight infections like healthy lymphocytes do, and as they increase in number they begin to crowd out healthy blood cells, which can disrupt the ability of the healthy blood cells to carry out their regular functions.View all videos