Leukemia – Acute Lymphocytic – All

There are three different types of lymphocytes: T cells, B cells, and natural killer (NK) cells. Generally, T cells fight infections by activating other cells in the immune system and by destroying infected cells, B cells make antibodies, and NK cells fight microbial cells and cancer cells. Approximately 85% of ALL cases are the B-cell subtype, and about 15% are of T-cell type. The NK-cell subtype is quite rare.

In people with ALL, the abnormal cells crowd other types of cells in the bone marrow, preventing the production of red blood cells (which carry oxygen), other types of white blood cells, and platelets (blood components needed for clotting). This means that people with ALL may be anemic (because they do not have enough red blood cells), susceptible to infection (because they do not have enough of the type of white blood cells called neutrophils that fight bacteria), and bruise or bleed easily (because of a low level of platelets). Lymphoblasts may also collect in a person’s lymph tissues and cause swelling of the glands. Some cells may invade other organs, including the brain, liver, spleen, or the testicles in men.

The spread of ALL to other parts of the body does not mean the cancer is in an advanced stage, because acute leukemia is usually found throughout the body when it is diagnosed.