Pediatric Leukemias: Chemotherapy, Radiation, and Bone Marrow Transplants

Pediatric Leukemias: Chemotherapy, Radiation, and Bone Marrow Transplants

Nurse practitioner Maura Byrnes-Casey with a young patient.

Nurse practitioner Maura Byrnes-Casey with a young patient.

Specialists from all areas of leukemia care work together to design a treatment plan especially for your child. Bringing together experts in chemotherapy, immunotherapy, bone marrow transplantation, and quality-of-life issues helps us choose the combination of therapies that will most effectively treat the leukemia and provide your child with the best outcome possible.

Standard treatment for ALL is typically divided into several phases: induction, consolidation, and maintenance.

Remission Induction for Childhood Leukemias

In the first stage of treatment for leukemias, doctors work to put the disease into remission. This stage, known as remission induction, takes about four weeks.

Remission induction for both ALL and AML involves the use of chemotherapy medications, which kill the leukemic cells and stop abnormal white blood cells from growing. Your child may receive a combination of several chemotherapy medications. Each medication targets leukemic cells in a different way, in case the cells are resistant to a particular treatment. Our team works to treat children with the most-effective dose and combination of chemotherapy to maximize the benefit and minimize the risk of long-term side effects.

Additional medications will also be given as support for your child, to minimize nausea, constipation, and kidney damage from the breakdown of leukemic cells.

Many children can receive remission induction treatment as outpatients in our Pediatric Day Hospital. However, children are at a high risk of infection during this process. Some children remain in our inpatient unit for three to four weeks to receive intravenous antibiotics for fevers or infections because they do not have enough normal white blood cells to fight infections. Once healthy white blood cells return, these children can be discharged and receive further treatment as outpatients in the Pediatric Day Hospital.

After the first few weeks of remission induction therapy, your child’s strength and stamina will gradually return, but he or she might not be able to return to school for several months due to an increased risk of infections. Subsequent inpatient hospital visits may be necessary to administer additional chemotherapy and treat infections that result from low white blood cell counts. Our doctors and nurses will provide more specific guidelines on what to expect based on your child’s specific treatment and response.

Consolidation and Maintenance Therapy

After the leukemia is in remission, a child is given additional treatment at home and as an outpatient to kill any lingering cancer cells.

Consolidation Therapy

In most children, an undetectable pool of leukemic cells can “hide” in the central nervous system, which includes the brain, spinal cord, or spinal fluid. During consolidation therapy, these cells are targeted by chemotherapy drugs injected directly into the fluid surrounding the spinal column. For this procedure, known as a lumbar puncture, the child is briefly placed under anesthesia.

A small percentage of children may also receive radiation therapy to the head, called cranial irradiation, to treat any leukemic cells in the central nervous system or to prevent the disease from spreading there. This treatment is for children who are at a very high risk of cancer recurrence or have central nervous system (meningeal) leukemia when they are diagnosed.

Maintenance Therapy

Following consolidation therapy, your child will receive maintenance therapy to further reduce the chance of a recurrence. Maintenance therapy is less intensive for standard-risk children than for those who have a higher risk of the leukemia returning. It typically involves a combination of chemotherapy drugs to target cells that may be dormant, or “hiding,” anywhere in the body. Maintenance therapy can last six months for some children with AML, or two to three years for a child with ALL.

Most children with ALL are cured with maintenance therapy. Fewer than 20 percent of high-risk patients and fewer than 10 percent of standard-risk patients will experience a cancer relapse. Most who relapse will return to a second remission with another intensive remission induction therapy.

Bone Marrow Transplantation

Children with AML or ALL who will not be cured with chemotherapy alone may benefit from a bone marrow transplant, also called a stem cell transplant. At Memorial Sloan Kettering, we look to identify these characteristics at the time the child is diagnosed. If we determine that your child needs a transplant, we will work with the bone marrow transplant team to identify potential donors for him or her, both in the family and in the general population through the National Marrow Donor Program.

Innovative Treatments

If your child has relapsed more than once, his or her leukemic cells are likely resistant to previously used treatments. However, these cells might still respond to other treatments. Experts at Memorial Sloan Kettering have evaluated many new combinations of drugs for children who relapse.

One promising treatment we have identified includes combinations of chemotherapy with drugs that have been used extensively to treat other types of cancer. (1) With this treatment, 30 to 40 percent of children who have resistant leukemia have achieved another remission. For children with resistant disease, we are also studying a new medication — called clofarabine — alone and in combination with other chemotherapies. This treatment has successfully returned many children into remission. (2), (3), (4)

For children who are not responding to therapies that are known to be effective, our team can often offer new treatments through clinical trials.

Monitoring for Disease

Successfully treating leukemia means that we carefully monitor the levels of disease remaining throughout different points of your child’s treatment. We can check for very, very low levels of leukemia — also called minimal residual disease (MRD) — with specialized tests on blood or bone marrow.  One method we use to detect MRD levels is flow cytometry. MSK is one of a select few centers nationwide that has had its flow cytometry method for leukemia MRD testing validated by the Children’s Oncology Group. This means that we can test samples faster and with greater accuracy than other institutions, and as a result, can better customize treatments based on how your child is responding. In addition, MSK also offers leukemia patients next-generation sequencing to look even deeper for minute traces of cancer cells in the blood or bone marrow. Taken together, MSK offers an unparalleled level of precision in the detection of MRD for patients with leukemia.