There are usually four general phases of chemotherapy for children with acute lymphoblastic leukemia. Treatment typically takes two to three years to complete. Our oncologists, nurses, radiologists, psychologists, and wellness experts provide support for your family—from medical care to emotional and logistical assistance—during and after treatment.
During the induction phase of chemotherapy, the aim is to quickly eliminate as many leukemia cells as possible. The goal is that remission—when the signs and symptoms of cancer have disappeared—can be achieved after this first phase of treatment.
Induction generally begins during an initial hospital stay, when chemotherapy drugs are administered intravenously through a vein and by mouth. Most children are hospitalized for the first week of induction but may stay longer if infections or other complications occur. Your child then continues to take the medication at home with frequent visits to our outpatient center at the Stephen D. Hassenfeld Children’s Center for Cancer and Blood Disorders.
Children with acute lymphoblastic leukemia typically go into remission after the four-week induction stage. During this stage, your child’s response to the treatment is measured by how fast the cancer cells disappear. Tests such as flow cytometry, which identifies white blood cell types in blood and bone marrow, can help your child’s doctor detect the presence of “minimal residual disease”—often called simply MRD—when small amounts of leukemia can be detected among normal blood cells. The result of these tests can lead to further tailoring of treatment to your child’s needs.
Consolidation or Intensification
In the consolidation or intensification phase, your child’s doctor administers another course of chemotherapy several times a week for a period of up to eight weeks. This phase is designed to kill cancer cells that did not respond to the chemotherapy drugs used during induction. It usually doesn’t require a hospital stay, but children are sometimes admitted for complications such as fever or infection.
The more intense the chemotherapy schedule used during consolidation, the greater the odds of neutropenia, which is an unusually low number of normal cells called neutrophils that help the immune system fight infection.
Interim Maintenance and Delayed Intensification
After consolidation is complete, a combination of chemotherapy drugs is given to your child in specific doses and sequences based on his or her risk group defined at diagnosis. During these phases of treatment, occasional hospitalization may be needed to manage side effects, which can include fever, lethargy, low blood cell levels, nausea, or vomiting.
Interim maintenance lasts about eight weeks and can require periodic hospitalization for chemotherapy. The next phase, delayed intensification, includes a shortened version of the induction and consolidation cycles to prevent resistant cells from appearing and growing.
After these initial, more intensive chemotherapy phases, maintenance chemotherapy is given by mouth and IV to prevent leukemia from returning. Maintenance therapy is given as an outpatient treatment periodically for about two years in girls and three years in boys. Because many of the side effects typically experienced in earlier stages of treatment are less common during maintenance, children can usually return to school if they have not already done so.