Childhood acute lymphoblastic leukemia (also called acute lymphocytic leukemia or ALL) is a cancer of the blood and bone marrow. This type of cancer usually gets worse quickly if it is not treated. It is the most common type of cancer in children.
Normally, the bone marrow produces stem cells (immature cells) that develop into mature blood cells. There are 3 types of mature blood cells:
In ALL, too many stem cells develop into a type of white blood cell called lymphocytes. These lymphocytes may also be called lymphoblasts or leukemic cells. There are 3 types of lymphocytes:
In ALL, 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 lead to infection, anemia, and easy bleeding.
This summary is about acute lymphoblastic leukemia. Refer to the following PDQ summaries for information on other types of leukemia:
Three of the subgroups of ALL are based on the type of blood cell that is affected, whether there are certain changes in the chromosomes, and age at diagnosis:
These subgroups are treated differently from other types of ALL.
Exposure to radiation and family history may affect the risk of developing childhood ALL.Anything that increases your risk of getting a disease is called a risk factor. Possible risk factors for ALL include the following:
These and other symptoms may be caused by childhood ALL. Other conditions may cause the same symptoms. A doctor should be consulted if any of the following problems occur:
The following tests and procedures may be used:
The prognosis (chance of recovery) and treatment options depend on:
The extent or spread of cancer is usually described as stages. For childhood acute lymphoblastic leukemia (ALL), risk groups are used instead of stages. The following tests and procedures may be used to determine the risk group:
Risk groups are described as:
It is important to know the risk group in order to plan treatment.
Recurrent childhood ALL is cancer that has recurred (come back) after it has been treated. The leukemia may come back in the blood and bone marrow, brain, testicles, spinal cord, or in other parts of the body.
Different types of treatment are available for children with acute lymphoblastic leukemia (ALL). Some treatments are standard (the currently used treatment), and some are being tested in clinical trials. A treatment clinical trial is a research study meant to help improve current treatments or obtain information on new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment.
Because cancer in children is rare, taking part in a clinical trial should be considered. Clinical trials are taking place in many parts of the country. Information about ongoing clinical trials is available from the NCI Web site. Choosing the most appropriate cancer treatment is a decision that ideally involves the patient, family, and health care team.
Children with ALL should have their treatment planned by a team of doctors with expertise in treating childhood leukemia.Your child's treatment will be managed by a pediatric oncologist, a doctor who specializes in treating children with cancer. The pediatric oncologist may refer you to other pediatric doctors who have experience and expertise in treating children with leukemia and who specialize in certain areas of medicine. These may include the following specialists:
Regular follow-up exams are very important. Side effects can result from treatment long after it ends. These are called late effects. Radiation therapy to the head may affect the child's developing brain and may cause second cancers, especially brain tumors. Early diagnosis and treatment of these secondary brain tumors may help lower the risk from these brain tumors. See the PDQ summary on Late Effects of Treatment for Childhood Cancer.
The treatment of childhood ALL usually has 3 phases.The treatment of childhood ALL is done in phases:
Bone marrow biopsy and aspirates are done throughout all phases to see how well the leukemia is responding to treatment.
Treatment called central nervous system (CNS) sanctuary therapy is usually given during each phase of therapy. Because chemotherapy that is given by mouth or injected into a vein may not reach leukemia cells in the CNS (brain and spinal cord), the cells are able to find “sanctuary” (hide) in the CNS. Intrathecal chemotherapy and radiation therapy are able to reach leukemia cells in the CNS and are given to kill the leukemia cells and prevent the cancer from recurring (coming back). CNS sanctuary therapy is also called CNS prophylaxis.
Three types of standard treatment are used:Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping the cells from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is placed directly into the spinal column (intrathecal), an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas (regional chemotherapy). Combination chemotherapy is treatment using more than one anticancer drug. The way the chemotherapy is given depends on the type of the cancer being treated.
Intrathecal chemotherapy may be used to treat childhood ALL that has spread, or may spread, to the brain and spinal cord. When used to prevent cancer from spreading to the brain and spinal cord, it is called central nervous system (CNS) sanctuary therapy or CNS prophylaxis. Intrathecal chemotherapy is given in addition to chemotherapy by mouth or vein.
Radiation therapyRadiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells. There are two types of radiation therapy. External radiation therapy uses a machine outside the body to send radiation toward the cancer. Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer. External radiation therapy may be used to treat childhood ALL that has spread, or may spread, to the brain and spinal cord. When used this way, it is called central nervous system (CNS) sanctuary therapy or CNS prophylaxis.
Chemotherapy with stem cell transplantStem cell transplant is a method of giving chemotherapy and replacing blood-forming cells destroyed by the cancer treatment. Stem cells (immature blood cells) are removed from the blood or bone marrow of a donor and are frozen and stored. After the chemotherapy is completed, the stored stem cells are thawed and given back to the patient through an infusion. These reinfused stem cells grow into (and restore) the body's blood cells. A stem cell transplant using stem cells from a donor who is not related to the patient is being studied in clinical trials.
New types of treatment are being tested in clinical trials. These include the following:High-dose chemotherapy is giving high doses of anticancer drugs to kill cancer cells. This treatment often causes the bone marrow to stop making blood cells and can cause other serious side effects. High-dose chemotherapy is usually followed by stem cell transplant to restore the bone marrow. Clinical trials are studying high-dose chemotherapy for certain patients, including children whose ALL does not go into remission after induction therapy.
Other drug therapyImatinib mesylate (Gleevec) is a type of anticancer drug called a tyrosine kinase inhibitor. It blocks the enzyme, tyrosine kinase, that causes stem cells to develop into more white blood cells (granulocytes or blasts) than the body needs.
This summary section refers to specific treatments under study in clinical trials, but it may not mention every new treatment being studied. Information about ongoing clinical trials is available from the NCI Web site.
Standard treatment of childhood acute lymphoblastic leukemia (ALL) during the induction phase is usually combination chemotherapy with intrathecal chemotherapy. Radiation therapy to brain may also be given.
Standard treatment of childhood ALL during the consolidation/intensification phase is usually combination chemotherapy with intrathecal chemotherapy. Radiation therapy to brain may also be given.
Standard treatment of childhood ALL during the maintenance phase is usually combination chemotherapy with intrathecal chemotherapy. Radiation therapy to brain may also be given.
Some of the treatments being studied in clinical trials for childhood ALL include the following:
Information about these and other clinical trials is available from the NCI Web site.
Standard treatment of T-cell childhood acute lymphoblastic leukemia (ALL) is usually combination chemotherapy with intrathecal chemotherapy and may include radiation therapy to the brain. One of the treatments being studied in clinical trials for T-cell childhood ALL is a new kind of anticancer drug.
Treatment of infants with ALL is usually a clinical trial of systemic chemotherapy with intrathecal chemotherapy.
Standard treatment of Philadelphia chromosome-positive childhood ALL is usually a stem cell transplant using stem cells donated by a brother or sister. One of the treatments being studied in clinical trials for Philadelphia chromosome-positive childhood ALL is imatinib mesylate (Gleevec).
This summary section refers to specific treatments under study in clinical trials, but it may not mention every new treatment being studied. Information about ongoing clinical trials is available from the NCI Web site.
Standard treatment of recurrent childhood ALL may include the following:
Some of the treatments being studied in clinical trials for recurrent childhood ALL include the following:
Information about these and other ongoing clinical trials is available from the NCI Web site.