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Treatments for childhood leukemia
The healthcare team will create a treatment plan just for your child with leukemia. It will be based on the child’s needs and may include a combination of different treatments. When deciding which treatments to offer for childhood leukemia, the healthcare team will consider the:
- type and subtype of leukemia
- prognostic factors
- level of risk
- chromosome and gene changes within the leukemia cells, or blasts
- child’s age
- child’s overall health
- response to treatment
Some children with leukemia may be very ill when they are first diagnosed. They may be very anemic or at risk for infection and bleeding because of low blood counts. Treatments for leukemia can also cause side effects. Supportive therapy with antibiotics, growth factors and blood products may be used to treat or help prevent these conditions.
Treatment options for childhood leukemia
The following treatments may be offered for childhood leukemia.
Chemotherapy
Chemotherapy is the main treatment for childhood leukemia. It is also given to prevent or treat the spread of leukemia to the brain or spinal cord (called the central nervous system, or CNS).
Radiation therapy
Radiation therapy is sometimes used to treat childhood leukemia. It may be used to prevent or treat the spread of leukemia to the CNS. It may be used to treat leukemia that has spread to the testicles. Radiation therapy may also be used to prepare for stem cell transplant.
Stem cell transplant
Stem cell transplant may be used to treat certain subtypes of childhood leukemia that are more likely to recur or that relapse soon after remission.
Targeted therapy
Targeted therapy is sometimes used to treat certain subtypes of childhood leukemia.
Supportive therapy
Supportive therapy is used to treat symptoms of leukemia or manage complications of treatment. It may include giving antibiotics and antifungals, blood products, growth factors and other drugs.
Follow-up care
Follow-up after treatment is finished allows the healthcare team to watch for a possible recurrence of leukemia and for any late effects of treatment. Children with childhood leukemia should have regular follow-up visits, especially in the first few years after treatment.
Response to treatment
How well leukemia responds to treatment helps doctors determine level of risk and plan future care. Doctors may use the following terms to describe childhood leukemia when discussing treatment and response to treatment.
Untreated disease
Untreated leukemia is newly diagnosed. It hasn’t been treated yet, other than to relieve symptoms.
The doctor will check the blood and bone marrow to see if there are any leukemia cells, or blasts. Untreated leukemia is defined by:
- abnormal complete blood count (CBC) and leukemia cells may be in the peripheral blood
- abnormal bone marrow (more than 25% of the cells in the bone marrow are leukemia cells)
- there are signs and symptoms of childhood leukemia
Disease in remission
A child is usually said to be in complete remission, or had a complete response to treatment, if there is no evidence of leukemia after 4–6 weeks of induction chemotherapy. It is called induction chemotherapy because it is the first in a series of treatments.
Complete remission or complete response is broadly defined by:
- normal CBC
- less than 5% of the cells in the bone marrow are leukemia cells, or blasts
- there are no general signs or symptoms of childhood leukemia
- there are no signs or symptoms of leukemia in the brain and spinal cord (called the central nervous system, or CNS) or other parts of the body
New testing techniques, such as flow cytometry or polymerase chain reaction (PCR), can accurately measure leukemia cells in the bone marrow after treatment, or minimal residual disease (MRD). Remission may be defined as less than 0.10%–0.01% leukemia cells in the bone marrow.
Minimal residual disease (MRD)
After treatment, there may still be leukemia cells, or blasts, in the bone marrow. Standard lab tests, such as microscopy, may not find these leukemia cells. But more sensitive tests, such as flow cytometry or polymerase chain reaction (PCR), find these leukemia cells. Disease that can only be found using more sensitive tests is called minimal residual disease (MRD).
MRD can be used as a measure of response to treatment. Children with even small amounts of MRD may have a greater risk of recurrence than those with undetectable MRD.
Active disease
Active disease means that more than 5% of the cells in the bone marrow are leukemia cells, or blasts. This term may be used for during or after treatment if the disease has come back (recurred, or relapsed).
Recurrent disease
Recurrent, or relapsed, disease refers to leukemia that comes back after it was in remission following treatment. A child is considered to have recurrent leukemia if more than 5% of the cells in the bone marrow are leukemia cells, or blasts.
Leukemia may come back in the blood, bone marrow or other parts of the body such as the brain or spinal cord (called the central nervous system, or CNS) or the testicles in boys.
Refractory disease
Refractory means the cancer is resistant to treatment or the treatment isn’t working. A child is considered to have refractory disease if the leukemia doesn’t go into complete remission after treatment.
Central nervous system (CNS) disease
Central nervous system (CNS) disease is when leukemia has spread to the brain or spinal cord. It is defined by the number of white blood cells (WBCs) in the cerebrospinal fluid (CSF).
CNS disease may be described as one of the following:
- CNS 1 – no leukemia cells, or blasts, in the CSF
- CNS 2 – WBC count is less than 5/mL with leukemia cells, or blasts, in the CSF
- CNS 3 – WBC count is 5/mL or greater with leukemia cells, or blasts, in the CSF or signs that leukemia has spread to the CNS
Clinical trials
Clinical trials investigate new and better ways to prevent, find and treat cancer. Many children with cancer will be offered treatment in a clinical trial. Find out more about clinical trials.
Questions to ask about treatment
To make the decisions that are right for your child, ask the healthcare team questions about treatment.
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