Childhood Acute Lymphoblastic Leukemia
Childhood acute lymphoblastic leukemia is the most common cancer in children, occurring in one out of every 29,000 children in the United States each year. Today, approximately 85 percent of children with this type of leukemia will live five years or more after diagnosis. Treatment options depend on the subtype of the cancer and include chemotherapy, radiation therapy, and stem cell transplant.
What Is Childhood Acute Lymphoblastic Leukemia?
Acute lymphoblastic leukemia (ALL) is a cancer of the white blood cells, which are the cells in the body that normally fight infections. ALL is also called acute lymphocytic leukemia. Acute lymphoblastic leukemia accounts for about 3,800 new cases of leukemia each year. Although this type of leukemia is the most common type of leukemia in young children, it also affects adults.
Cancer in children and adolescents is rare. However, childhood acute lymphoblastic leukemia is the most common cancer in children, representing 23 percent of cancer diagnoses among children who are younger than 15 years of age. This type of leukemia occurs in about one out of every 29,000 children in the United States each year.
Understanding Blood Cells
Normally, the body produces bone marrow stem cells (immature cells) that develop into mature blood cells.
The three types of mature blood cells include:
- Red blood cells that carry oxygen and other materials to all tissues of the body
- White blood cells that fight infection and disease
- Platelets that help prevent bleeding by causing blood clots to form.
In acute lymphoblastic leukemia, too many stem cells develop into a type of white blood cell called lymphocytes. These lymphocytes may also be called lymphoblasts or leukemia cells.
The three types of lymphocytes include:
- B lymphocytes that make antibodies to help fight infection
- T lymphocytes that help B lymphocytes make the antibodies that help fight infection
- Natural killer cells that attack cancer cells and viruses.
In acute lymphoblastic leukemia, the lymphocytes are not able to fight infection very well. Also, as the number of lymphocytes increases in the blood and bone marrow, there is less room for healthy white blood cells, red blood cells, and platelets. This may cause infection, anemia, and easy bleeding. Acute lymphoblastic leukemia can also spread to the central nervous system (brain and spinal cord).