Childhood Acute Myeloid Leukaemia (AML)

In the UK, around 2,300 people are diagnosed with AML each year. Of these, only 70 are children.

Children with Acute Myeloid Leukaemia (AML) produce too many immature cells (blast cells) which populate the blood and bone marrow. Over time, these abnormal cells will accumulate and begin to fill up the bone marrow, preventing it from producing healthy blood cells.

There are several different subtypes of AML, and the type your child has will depend on which type of myeloid cell is mainly being produced in excess. One important subtype is called acute promyelocytic leukaemia (APL or APML) and it makes up about one in 10 cases of AML.

You can watch Jenson’s story above.

What causes Childhood AML?

In most cases, there is no obvious cause of childhood AML, and both boys and girls have about the same likelihood of developing AML.

In the vast majority of cases, AML does not run in families. There have been very unusual family cases where AML affects more than one generation. This is very rare, and, in almost all cases, there is no cause for anxiety or for screening tests.

Down’s syndrome

There are some genetic conditions, such as Down’s syndrome, which can increase the chance of developing AML. This type of AML is treated differently to standard AML. If this is the case for your child, their consultant will provide detailed information. Children born with Down’s syndrome may also develop a leukaemia-like blood condition called transient abnormal myelopoiesis (TAM) which usually goes away without treatment.

What are the symptoms of Childhood Information?

The majority of children with AML will have symptoms when they are diagnosed. However, they are often difficult to spot as they can be confused and mistaken for symptoms of other, less serious illnesses.

If your child develops any new symptoms, they get worse or last longer than normal, contact your GP straight away.

Symptoms include:

  • Your child may feel more tired or breathless than normal
  • They may pick up infections more easily that last longer and are persistent
  • Unusual bruising and bleeding
  • Bone pain
  • Enlarged liver and spleen
  • Swollen gums

Some children with AML who have a very high white cell count may develop a condition called leukostasis, in which blood flow is slowed down because of thickening of the blood.

Because your child is more at risk of picking up an infection, contact your hospital team if they develop any of these symptoms:

  • A raised temperature (38°C or higher)
  • Coughing
  • Confusion or agitation
  • Rapid heartbeat and fast breathing
  • Shivering
  • Quickly becoming ill
  • Increased pain

Diagnosis of Childhood AML

If AML is suspected, your child will have a set of tests to confirm the diagnosis. If your child is diagnosed with AML, they will also have further tests to determine the right treatment for their cancer. It’s important that you know and understand your child’s diagnosis, so you can ask questions and be fully informed of what to expect. Your child’s consultant will be able to write it in the front of this booklet if that would help you.

Sometimes, test results can take a little while. This can be an anxious and worrying time but please remember that it is important that your child’s medical team reach the correct diagnosis so that they can receive the right treatment.

Tests may include:

  • Full Blood Count (FBC) – this is a simple blood test which measures the number of red cells, white cells and platelets in the blood.
  • Cytogenetics – Cytogenetics is the study of gene changes and investigates the genetic differences between AML cells and normal cells. Cytogenetic results are important for the WHO classification of AML and for risk classification.
  • Bone marrow samples – In most cases, your child’s doctor will take a bone marrow sample, where a small amount of bone marrow is taken from the hip bone using a fine needle (an aspirate), to look at the cells. They may also have a sample of bone marrow taken from the core using a larger needle (a trephine) to look at the structure of the bone marrow. This is performed under local anaesthetic or general anaesthetic in children.

Other tests which may be done include:

  • Lumbar puncture – in childhood AML, a sample of cerebrospinal fluid (CSF) is taken from the spine to see whether there are leukaemia cells in the nervous system. In AML, cells can get into the nervous system, which protects them from some treatment.
  • X-rays, ultrasound or scans (CT or MRI) – To monitor impact on organs of the body.

Blood tests and bone marrow samples will be repeated throughout treatment to monitor response.

Risk grouping

The most important part of classifying childhood AML is risk grouping. There are three risk groups in AML; high, standard and low risk and your child will be classified into a risk group based on the results of the tests they had at diagnosis. Risk grouping is a way of estimating how likely it is that treatment will be successful.

Children in the low risk group often do well following conventional treatment. Children in the high-risk category may need another type of treatment to achieve remission (no evidence of leukaemia cells in the body). However, many patients with high risk disease do respond well to treatment and sometimes, children in the low risk category do not. Your child’s risk group can change whilst they’re being treated, but their medical team will be able to provide ongoing updates relating to their condition.

Classification of AML

There are also two systems used to classify AML; the French-American-British (FAB), and the World Health Organisation (WHO) systems. The main difference is that the FAB system is mainly based on the appearance of the AML cells under the microscope, while the WHO system also uses information on the specific genetic changes in the AML cell (cytogenetics).

FAB classification

This is an older classification system but is still widely used and is particularly useful for initial classification before cytogenetic results are available. It is based mainly on the appearance of the AML cells under the microscope, sometimes using special stains. It does not relate to the severity of AML; in other words, M7 is not more severe than M0 or vice-versa.

FAB sub-types:

  • M0 – AML minimally differentiated
  • M1 – AML with minimal maturation
  • M2 – AML with maturation
  • M3 – Acute promyelocytic leukaemia
  • M4 – Acute myelomonocytic leukaemia
  • M4 eos – Acute myelomonocytic leukaemia with eosinophilia
  • M5 – Acute monocytic leukaemia
  • M6 – Acute erythroid leukaemia
  • M7 – Acute megakaryoblastic leukaemia

WHO classification

The WHO classification uses the same elements as the FAB system, but places an emphasis on cytogenetic data, which is not used in the FAB system. There are five main categories in the WHO system:

  • AML with recurrent genetic abnormalities – The abnormal cells have certain specific genetic changes.
  • AML with myelodysplasia-related changes – AML in patients previously diagnosed with MDS or with features similar to MDS.
  • Therapy-related myeloid neoplasms – AML in patients who have previously had chemotherapy and/or radiation therapy.
  • Myeloid proliferations related to Down’s syndrome – This only occurs in children.
  • AML not otherwise categorised – It does not fall into above categories.

What happens next?

Because AML progresses rapidly, virtually all children with AML start treatment soon after diagnosis. You can refuse treatment for your child at any time, but it is important that you understand clearly what might happen in this case. If your child’s haematologist does not think your child needs treatment, you cannot insist on starting treatment, but this is rare with AML. You can ask for a second opinion at any time. As far as possible, all decisions about your child’s treatment will take your wishes into account.

Treatment

Almost all patients will start treatment at, or soon after, the time of diagnosis. Childhood AML has better outcomes and is often curable with standard treatments compared to AML in adults. It is important to discuss the outlook (prognosis) with your child’s medical team, because it is affected by various factors such as the risk group.

The main reason a child may not start treatment would be if their general medical condition makes treatment too risky. This is very rare and if it affects your child you will be given full information by their specialist.

Treatment options for AML

Initial treatment of AML usually consists of chemotherapy and is divided into two phases – induction and consolidation.

Your child will receive most of their induction and consolidation treatment as an inpatient in hospital but may be able to go home between courses. They’ll be regularly monitored and may also receive blood and platelet transfusions or be treated for infections with antibiotics.

Conventional chemotherapy should take about five or six months and involves four courses of treatment each lasting four to six weeks. Two courses will be given during the induction phase to try and achieve remission. The other two courses will aim to prevent relapse.

Chemotherapy

Chemotherapy is the use of anti-cancer (cytotoxic) drugs to destroy cancer cells. Chemotherapy will also damage some normal cells, which means that there are side effects.

For children, chemotherapy is given as intensive treatment, which means higher doses and/or treatment over a longer period of time.  Some of the drugs are given directly into a vein (intravenously), others are given by mouth (orally), and others are injected into the spinal fluid (intrathecal).

Induction

Remission induction, often just called induction, is the use of chemotherapy to induce remission, ideally complete remission (CR) which means that no leukaemia cells can be found in the blood using standard tests. It is important to understand that remission, even CR, does not mean cure; if treatment stops at this point, almost all patients will relapse – their AML will return.

Consolidation

Consolidation treatment is given after remission induction to reduce the risk of a relapse (return of AML). In AML, cytarabine is used along with combinations of drugs that work in different ways, to reduce the risk of drug resistance. If your child has high risk AML, a stem cell transplant may be recommended as consolidation treatment (see below). Usually children only have a stem cell transplant if their AML returns after remission (relapse).

Stem cell transplant

A stem cell transplant involves the use of high-dose treatment to kill as many as possible of the leukaemia cells. This also destroys the bone marrow’s ability to make new blood cells, so the child is given healthy stem cells.

Children tend to do better than adults when they are given a stem cell transplant. However, it does require higher doses of chemotherapy and may have more severe side effects, which is why it is not done for all children.

Central Nervous System (CNS) AML

Sometimes, AML cells may be found in the cerebrospinal fluid (CSF), the fluid which surrounds the brain and the spinal cord; this is known as Central Nervous System (CNS) AML. CNS AML occurs in approximately five to ten in 100 children at the time of diagnosis or at relapse.

Children will normally have chemotherapy drugs injected into the CSF (intrathecal injection). Usually, this is enough to kill any leukaemia cells in the CSF, if any are found after two courses of intrathecal injections, your child may receive radiotherapy to prevent a relapse.

Treatment of relapse

Although most children with AML achieve remission, some will relapse. A relapse is a return of AML after a time without symptoms or signs of AML in blood counts. About 30% of children with AML will relapse.

For children who have relapsed, a repeat of remission induction followed by a stem cell transplant is recommended. If this happens to your child, the specialist will discuss the treatment options and likely outlook with you.

Supportive care

Supportive care is not directed at treating the disease but rather at controlling the symptoms and side effects caused by the disease.

This can include:

  • Antibiotics to treat bacterial infections
  • Antifungals to treat fungal infections
  • Eye drops
  • Blood and platelet transfusions
  • Heart scans to check that the chemotherapy is not affecting the heart in any way

Side effects

Unfortunately, treatments such as chemotherapy do come with some side effects as they damage healthy cells as well as cancer cells.

It’s difficult to predict exactly which side effects your child will experience as they vary with each drug. However, they are usually temporary.

Short term side effects

Short term side effects can last for a few days or weeks, but for some, can last for the duration of treatment. Side effects your child may experience include:

  • Hair loss
  • Nausea and vomiting
  • Weight loss
  • Fatigue
  • Infection – all patients with AML will at some point get an infection which requires treatment with antibiotics
  • Bleeding and bruising – chemotherapy can make your child more prone to bruising and bleeding

Long term side effects

Long term effects can be a result of chemotherapy but depends on the drugs used.

Loss of fertility

Some of the drugs used to treat AML can affect your child’s fertility in later life and their chances of conceiving in the future.

Your child’s medical team will talk to you about this in more detail before they start treatment and your child will have the chance to discuss this with their healthcare team as they mature and develop into adulthood.

It’s natural to worry about the effects of treatment on any children your child might have after their treatment. However, evidence from clinical studies has shown that any cancer treatment a parent has doesn’t lead to an increased risk of cancer or other health problems in their children.

What happens next?

Once your child’s treatment is finished, they’ll need to have regular check-ups at the hospital. These will be frequent at first, probably one to two months, then every few months until they become yearly at five years and onwards. The purpose of follow-up is to monitor your child and look for signs of relapse or complications.

If you notice any new symptoms or something is worrying you, you should contact your child’s medical team as soon as possible.

New treatments and treatments on the horizon

The number of new drugs available for treating childhood AML is increasing. There are several new types of drugs being studied for the treatment of AML. Most of these fall into the following groups:

  • Immunomodulatory drugs (IMiDs) – Immunomodulatory drugs have been widely used to treat other forms of blood cancer and are now being studied for use in AML. The way in which they work is not fully understood but they affect the immune system. They are mostly being studied in adults but, if results are promising, they may be used to treat childhood AML.
  • Histone deacetylase inhibitors – These are drugs which interfere with the way in which AML cells switch genes on and off.
  • Targeted therapies – These work in different ways but they all targeted to specifically attack the leukaemia cell, whereas most other chemotherapy drugs affect normal cells too. One type of targeted therapy is the use of antibodies to carry chemotherapy drugs directly to the leukaemia cell. Another type attacks weak points of leukaemia cells.
  • FLT3 and IDH inhibitors – FLT3 and IDH are two of the most common genes to become abnormal in AML. A number of drugs have been developed that target these genes.

Further downloads

We have free patient information available for Childhood AML patients.

You can download the booklets on our information pages here.

Alternatively, you can have the information delivered free of charge by requesting it through our resources page. 

Patient stories

Published date: April 2018

Review date: April 2020