Recurrent Childhood Acute Myeloid Leukemia

Recurrent childhood acute myeloid leukemia (AML) has recurred (come back) after it has been treated. The cancer may come back in the blood and bone marrow or in other parts of the body, such as the central nervous system (brain and spinal cord).

Treatment Option Overview

There are different types of treatment for children with acute myeloid leukemia (AML), chronic myelogenous leukemia (CML), juvenile myelomonocytic leukemia (JMML), transient myeloproliferative disorder (TMD), or myelodysplastic syndromes (MDS).

Different types of treatment are available for children with AML, CML, JMML, TMD, or MDS. 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 AML, CML, JMML, TMD, or MDS should have their treatment planned by a team of health care providers who are experts in treating childhood leukemia and other diseases of the blood.

Treatment will be overseen by a pediatriconcologist, a doctor who specializes in treating children with cancer. The pediatric oncologist works with other health care providers 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.
• Neurologist.
• Neuropathologist.
• Neuroradiologist.
• Pediatric nurse specialist.
• Social worker.
• Rehabilitation specialist.
• Psychologist.

Some cancer treatments cause side effects months or years after treatment has ended.

Regular follow-up exams are very important. Some cancer treatments cause side effects that continue or appear months or years after cancer treatment has ended. These are called late effects. Late effects of cancer treatment may include:

• Physical problems.
• Changes in mood, feelings, thinking, learning, or memory.
• Second cancers (new types of cancer).

Some late effects may be treated or controlled. It is important that parents of children who are treated for AML or other blood diseases talk with their doctors about the effects cancer treatment can have on their child. (See the PDQ summary on Late Effects of Treatment for Childhood Cancer for more information).

The treatment of childhood AML usually has two phases.

The treatment of childhood AML 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.
• Consolidation/intensification therapy: This is the second phase of treatment. It begins once the leukemia is in remission. The purpose of postremission therapy is to kill any remaining leukemia cells that may not be active but could begin to regrow and cause a relapse.

Treatment called central nervous system (CNS) sanctuary therapy may be given during the induction 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 is able to reach and kill leukemia cells in the CNS and prevent the cancer from recurring (coming back). CNS sanctuary therapy is also called CNS prophylaxis.

Seven types of standard treatment are used for childhood AML, childhood CML, JMML, TMD, or MDS.

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 cerebrospinal fluid (intrathecal chemotherapy), 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 cancer being treated.

In AML, the leukemia cells may spread to the brain and/or spinal cord. Anticancer drugs given by mouth or vein to treat AML cannot cross the blood-brain barrier and enter the fluid that surrounds the brain and spinal cord. Instead, an anticancer drug is injected into the fluid-filled space to kill leukemia cells that may have spread there. This is called intrathecal chemotherapy.

Intrathecal chemotherapy. Anticancer drugs are injected into the intrathecal space, which is the space that holds the cerebrospinal fluid (CSF, shown in blue). There are two different ways to do this. One way, shown in the top part of the figure, is to inject the drugs into an Ommaya reservoir (a dome-shaped container that is placed under the scalp during surgery; it holds the drugs as they flow through a small tube into the brain). The other way, shown in the bottom part of the figure, is to inject the drugs directly into the CSF in the lower part of the spinal column, after a small area on the lower back is numbed.

See Drugs Approved for Acute Myeloid Leukemia for more information.

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 AML 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.

Stem cell transplantation

Stem cell transplant is a way of giving chemotherapy and replacing blood-forming cells that are abnormal or destroyed by the cancer treatment. Stem cells (immature blood cells) are removed from the blood or bone marrow of the patient or 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.

Stem cell transplant (Step 1). Blood is taken from a vein in the arm of the donor. The patient or another person may be the donor. The blood flows through a machine that removes the stem cells. Then the blood is returned to the donor through a vein in the other arm.

Stem cell transplant (Step 2). The patient receives chemotherapy to kill blood-forming cells. The patient may receive radiation therapy (not shown).

Stem cell transplant (Step 3). The patient receives stem cells through a catheter placed into a blood vessel in the chest.

Targeted therapy with a tyrosine kinase inhibitor

Targeted therapy is a treatment that uses drugs or other substances to identify and attack specific cancer cells without harming normal cells. Tyrosine kinase inhibitor (TKI) therapy is a type of targeted therapy that blocks signals needed for tumors to grow. TKIs blocks the enzyme, tyrosine kinase, that causes stem cells to develop into more white blood cells (granulocytes or blasts) than the body needs. Imatinib (Gleevec) is one of the TKIs used to treat childhood CML.

TKIs may be used in combination with other anticancer drugs as adjuvant therapy (treatment given after the initial treatment, to lower the risk that the cancer will come back).

See Drugs Approved for Myeloproliferative Disorders for more information.

Other drug therapy

Lenalidomide may be used to lessen the need for transfusions in patients who have myelodysplastic syndromes caused by a specific chromosome change.

Arsenic trioxide and all-trans retinoic acid (ATRA) are anticancer drugs that kill leukemia cells, stop the leukemia cells from dividing, or help the leukemia cells mature into white blood cells. These drugs are used in the treatment of a subtype of AML called acute promyelocytic leukemia (APL).

See Drugs Approved for Acute Myeloid Leukemia for more information.

Watchful waiting

Watchful waiting is closely monitoring a patient's condition without giving any treatment until symptoms appear or change. It is sometimes used to treat MDS or TMD.

Supportive care

Supportive care is given to lessen the problems caused by the disease or its treatment. Supportive care may include the following:

• Transfusiontherapy: A way of giving red blood cells, white blood cells, or platelets to replace blood cells destroyed by disease or cancer treatment. The blood may be donated from another person or it may have been taken from the person earlier and stored until needed.
• Drug therapy, such as antibiotics.
• Leukapheresis: A procedure in which a special machine is used to remove white blood cells from the blood. Blood is taken from the patient and put through a blood cell separator where the white blood cells are removed. The rest of the blood is then returned to the patient's bloodstream.

New types of treatment are being tested in clinical trials.

This summary 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.

Targeted therapy

Targeted therapy is a type of treatment that uses drugs or other substances to identify and attack specific cancer cells without harming normal cells. Monoclonal antibodies, proteasome inhibitors, tyrosine kinase inhibitors, and natural killer (NK) cells are types of targeted therapies being studied in the treatment of childhood AML.

Monoclonal antibody therapy uses antibodies made in the laboratory, from a single type of immune system cell. These antibodies can identify substances on cancer cells or normal substances that may help cancer cells grow. The antibodies attach to the substances and kill the cancer cells, block their growth, or keep them from spreading. Monoclonal antibodies are given by infusion. They may be used alone or to carry drugs, toxins, or radioactive material directly to cancer cells. Monoclonal antibodies may be used in combination with chemotherapy as adjuvant therapy.

Proteasome inhibitors break down proteins in cancer cells and kill them. Bortezomib is a proteasome inhibitor used to treat childhood acute promyelocytic leukemia.

Sorafenib is a tyrosine kinase inhibitor being studied in the treatment of childhood AML.

Natural killer (NK) cells are white blood cells that can kill tumor cells. These may be taken from a donor and given to the patient by infusion to help kill leukemia cells.

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.

Patients can enter clinical trials before, during, or after starting their cancer treatment.

Some clinical trials only include patients who have not yet received treatment. Other trials test treatments for patients whose cancer has not gotten better. There are also clinical trials that test new ways to stop cancer from recurring (coming back) or reduce the side effects of cancer treatment.

Clinical trials are taking place in many parts of the country. See the Treatment Options section that follows for links to current treatment clinical trials. These have been retrieved from NCI's listing of clinical trials.

Follow-up tests may be needed.

Some of the tests that were done to diagnose the cancer or to find out the stage of the cancer may be repeated. Some tests will be repeated in order to see how well the treatment is working. Decisions about whether to continue, change, or stop treatment may be based on the results of these tests. This is sometimes called re-staging.

Some of the tests will continue to be done from time to time after treatment has ended. The results of these tests can show if your condition has changed or if the cancer has recurred (come back). These tests are sometimes called follow-up tests or check-ups.