What are types of treatment for childhood acute lymphoblastic leukemia?
What are types of treatment for childhood acute lymphoblastic leukemia?
There are different types of treatment for childhood acute lymphoblastic leukemia (ALL).
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. Some clinical trials are open only to patients who have not started treatment.
Children with ALL should have their treatment planned by a team of doctors with expertise in treating childhood leukemia.
Treatment will be overseen by a pediatric oncologist, a doctor who specializes in treating children with cancer. The pediatric oncologist works with other pediatric health professionals who are experts in treating children with leukemia and who specialize in certain areas of medicine. These may include the following specialists:
- Hematologist
- Medical oncologist
- Pediatric surgeon
- Radiation oncologist
- Endocrinologist
- Neurologist
- Pathologist
- Radiologist
- Pediatric nurse specialist
- Social worker
- Rehabilitation specialist
- Psychologist
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 cause changes in mood, feelings, thinking, learning, or memory. Late effects of treatment for ALL also include the risk of second cancers (new types of cancer), especially brain tumors. Early diagnosis and treatment of these secondary brain tumors may help lower the risk from these brain tumors. Children younger than 4 years have a higher risk of side effects from radiation therapy to the brain. It is important to talk with your child's doctors about the possible late effects caused by some treatments.
The treatment of childhood ALL usually has 3 phases.
The treatment of childhood ALL is done in phases:
- Induction therapy: This is the first phase of treatment. Its purpose is to kill the leukemia cells in the blood and bone marrow. This puts the leukemia into remission. This is also called the remission induction phase.
- Consolidation /intensification therapy: This is the second phase of therapy. It begins once the leukemia is in remission. The goal of consolidation/intensification therapy is to kill any remaining leukemia cells that may not be active but could begin to regrow and cause a relapse.
- Maintenance therapy: This is the third phase of treatment. The goal is to kill any remaining leukemia cells that may regrow and cause a relapse. Often the cancer treatments are given in lower doses than those used for induction and consolidation/intensification therapy. This is also called the continuation therapy phase.
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.
Four types of standard treatment are used:
Chemotherapy
Chemotherapy is a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them 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 or high doses of chemotherapy injected into a vein 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. CNS sanctuary therapy is given in addition to chemotherapy by mouth or vein that is intended to kill leukemia cells in the rest of the body. All children with ALL receive CNS sanctuary therapy as part of their treatment.
Radiation therapy
Radiation therapy is a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing. 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.
Because radiation therapy to the brain can affect growth and brain development in young children, many children with ALL are treated without radiation therapy. Radiation therapy to the brain and spinal cord is sometimes used as CNS sanctuary therapy to treat children and teenagers in the high risk group. Clinical trials are studying new ways of using radiation therapy that may have fewer side effects, including giving lower doses of radiation.
Chemotherapy with stem cell transplant
Stem cell transplant is a method of giving very high doses of chemotherapy and sometimes radiation therapy, and then replacing the blood-forming cells destroyed by the cancer treatment. Stem cells (immature blood cells) are removed from the blood or bone marrow of a donor. After the patient receives very high doses of chemotherapy and sometimes radiation therapy, the donor's stem cells are given back to the patient through an infusion. These reinfused stem cells grow into (and restore) the patient's blood cells. A stem cell transplant may use stem cells from a donor who is or is not related to the patient.
Stem cell transplant is rarely used as initial treatment for children and teenagers with ALL. It is used more often as part of treatment for ALL that relapses (comes back after treatment).
Targeted therapy
Targeted therapy is a treatment that uses drugs or other substances to identify and attack specific cancer cells without harming normal cells.
Tyrosine kinase inhibitors (TKIs) are targeted therapy drugs that block the enzyme, tyrosine kinase, which causes stem cells to become more white blood cells or blasts than the body needs. For example, imatinib mesylate (Gleevec) is a TKI used in the treatment of children with Philadelphia chromosome -positive ALL.
New types of treatment are being tested in clinical trials.
This section describes treatments that are being studied in clinical trials. It may not mention every new treatment being studied. Information about clinical trials is available from the NCI Web site.
High-dose chemotherapy
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 and children whose leukemia comes back after treatment (relapses).
Targeted therapy
Targeted therapy is a treatment that uses drugs or other substances to identify and attack specific cancer cells without harming normal cells.
New kinds of targeted therapies are being studied in the treatment of childhood ALL.
Patients may want to think about taking part in a clinical trial.
For some patients, taking part in a clinical trial may be the best treatment choice. Clinical trials are part of the cancer research process. Clinical trials are done to find out if new cancer treatments are safe and effective or better than the standard treatment.
Many of today's standard treatments for cancer are based on earlier clinical trials. Patients who take part in a clinical trial may receive the standard treatment or be among the first to receive a new treatment.
Patients who take part in clinical trials also help improve the way cancer will be treated in the future. Even when clinical trials do not lead to effective new treatments, they often answer important questions and help move research forward.