AML is an overproduction of immature myeloid white blood cells (blast cells). Cells that have started to show features of myeloid cells are said to show differentiation. Cells that do not show signs of becoming a particular type of white blood cell are known as undifferentiated.
There are different sub-types of AML. Knowing this is important to help doctors decide on the best treatment.
Causes
The exact cause of AML is unknown. Research is going on all the time into possible causes of this disease. Children with certain genetic disorders, such as Down’s syndrome or Li-Fraumeni syndrome, are known to have a higher risk of developing leukaemia. Brothers and sisters of a child with AML have a slightly increased risk of developing AML themselves, although this risk is still very small. Children with bone marrow failure conditions may have an increased risk of developing AML.
AML, like all types of cancer, is not infectious and cannot be passed on to other people. It is important to remember that nothing you have done has caused your child’s cancer.
Signs and symptoms
As the leukaemia cells multiply in the bone marrow, the production of normal blood cells is reduced. Children may:
- become tired and lethargic
- develop bruises
- take longer to stop bleeding
- have bleeding gums or heavy nosebleeds
- have a purplish rash on the skin that does not disappear when you press a glass against it
- have infections
- develop fevers and sweating, especially at night.
- feel unwell and have aches and pains in the limbs
- have swollen lymph glands
At first, the symptoms may be like those of a viral infection. This can make it hard to diagnose but over time the diagnosis usually becomes clear.
How AML is diagnosed
A variety of tests and investigations may be needed to diagnose AML. A blood test usually shows low numbers of normal white blood cells and the presence of the abnormal leukaemia cells. A sample is also tested to look for any abnormal genetic changes and measurable residual disease (MRD) analysis.
There have been significant advances in understanding the genetic changes in leukaemia cells. These changes, (seen in about 75% of cases) are used to identify your child’s subtype of leukaemia, help doctors to predict their response to treatment and monitor the cancer. As understanding of the genetic changes improves, it is likely that this will help to guide treatment in the future.
A test called a lumbar puncture is done to see if the spinal fluid contains any leukaemia cells. A chest X-ray is also done, which will show if there are any enlarged glands in the chest. Other tests may be necessary, depending on your child’s symptoms.
These tests will help to identify the precise type of leukaemia and help doctors decide on the best treatment. Any tests and investigations that your child needs will be explained to you.
Treatment
The aim of treatment for AML is to destroy the leukaemia cells and enable the bone marrow to work normally again. Chemotherapy is the main treatment for AML.
Chemotherapy uses anti-cancer drugs to destroy cancer cells. It is given according to a treatment plan (often called a protocol or regimen). The treatment is given in several phases, or ‘blocks’, which are explained below.
Induction
This phase involves intensive treatment, aimed at destroying as many leukaemia cells as possible. It usually involves two courses (cycles) of a combination of chemotherapy drugs.
A bone marrow test will be taken after the first course of chemotherapy to confirm whether or not your child still has leukaemia. The sample that is taken is looked at under a microscope and when there is no evidence of leukaemia, the child’s condition is referred to as being in ‘remission’.
Consolidation treatment
After the first two courses of chemotherapy, if your child is in remission, further treatment is based on the results of the genetic and MRD tests on the bone marrow. Your child’s doctor will explain this to you in more detail. This phase of the treatment aims to destroy any leukaemia cells that may be left and to help stop the AML from coming back. Most children receive four courses (cycles) of chemotherapy in total.
Bone marrow transplant
Children at high risk of AML coming back following standard chemotherapy will have a bone marrow transplant to reduce the risk. This will usually be performed after 2 or 3 courses of chemotherapy when the child is in remission. Children in this group are identified based on the results of the genetic testing on the bone marrow and how the AML has responded to treatment. Children whose leukaemia returns after conventional treatment will also need a bone marrow transplant.
Central nervous system (CNS) treatment
AML may sometimes develop in the brain and spinal cord. This can be prevented by injecting chemotherapy drugs directly into the spinal fluid during a lumbar puncture (intrathecal chemotherapy). Intrathecal chemotherapy is usually given with the lumbar puncture performed at the time of diagnosis and before the second course of chemotherapy. Sometimes a more intensive treatment is needed, and the intrathecal drugs are given more frequently until all the regular chemotherapy has been completed.
Follow-up care
Many children with AML are cured. If the leukaemia comes back after initial treatment, it usually does so within the first three years. Further treatment can then be given.
Long-term side effects (late side effects) are rare, and most children with AML grow and develop normally.
Once treatment has finished, the doctors will monitor your child closely with regular appointments to be sure that the cancer has not come back and there are no complications. After a while, you will not need to visit the clinic so often.
If you have specific concerns about your child’s condition and treatment, it’s best to discuss them with your child’s doctor, who knows the situation in detail.
Useful resources
This information is about acute myeloid leukaemia (AML) in children (age 0-14 years).Find out about acute myeloid leukaemia (AML) in teenagers and young adults (15-24 years)