What is acute lymphoblastic leukemia?

Acute lymphoblastic leukemia (ALL), sometimes called acute lymphocytic leukemia, is the most common form of leukemia found in children, accounting for about 30 percent of all pediatric cancer. ALL has one of the highest cure rates of all childhood cancers.

Acute lymphoblastic leukemia affects the immature forms of white blood cells, called lymphocytes. There are two basic types of lymphocytes, B-lymphocytes and T-lymphocytes, and their immature forms are the source of the two corresponding subsets of ALL, T-ALL and B- or pre-B ALL.

The job of lymphocytes is to identify and destroy foreign proteins in the body, such as bacteria and viruses. In ALL, the bone marrow makes too many immature lymphocytes (called lymphoblasts) that do not mature correctly. Immature blood cells (blasts) do not have the ability to fight infection. The lymphoblasts overproduce and crowd out normal blood-forming cells in the bone marrow.

Treatment for acute lymphoblastic leukemia

Treatment for acute lymphoblastic leukemia usually begins by addressing the signs and symptoms your child has, such as anemia, bleeding and/or infection. In addition, treatment for leukemia will include most of the following:

• Chemotherapy. Chemotherapy refers to medicines that help fight cancer. They are given by mouth, in the vein, in the muscle or under the skin.
• Intrathecal medications/chemotherapy. Intrathecal chemotherapy is chemotherapy that is injected into the spinal fluid to prevent or treat leukemia in the brain and spinal cord. Intrathecal medications/chemotherapy involves inserting medications through a needle into the fluid-filled space surrounding the spinal cord.
• Blood transfusions. Blood transfusions are used for patients who have anemia who cannot make their own red blood cells. Platelets are commonly transfused when platelet counts are low. Chemotherapy can cause anemia and low platelets, and patients often require transfusions
• Antibiotics. Antibiotics are used to prevent or treat infections.
• Placement of permanent line. When a central venous line is used to take blood or give medication, a plastic tube or catheter is inserted into a large vein in the chest, neck or arm. The use of a central line prevents a lot of needle sticks.
• Radiation therapy. Radiation therapy uses high-energy waves such as X-rays to kill or shrink cancer cells. It is rarely used to treat leukemia in the central nervous system or other places such as the eye or the testes.
• Blood and marrow transplantation. Blood and marrow transplantation consists of three steps: 1) collection of healthy stem cells from a donor without cancer or from the patient; 2) administration of high doses of chemotherapy and possibly radiation therapy to kill any remaining leukemia cells; and 3) infusion of the healthy stem cells through an intravenous line to produce normal blood-forming cells. Bone marrow or stem cell transplantation is commonly used to treat ALL that has not responded to chemotherapy, or that was found to have very high risk of relapse.
• Immunotherapy. Some children with certain forms of relapsed and refractory acute lymphoblastic leukemia may be candidates for CAR T-cell therapy, a form of immunotherapy.