Leukaemia factsheet


Leukaemia is cancer in the white blood cells and the body tissue that makes them called the bone marrow. It is the most common type of childhood cancer.

White blood cells are part of the immune system, which keeps your child’s body healthy and protects it from illness and infection.

In leukaemia, the bone marrow starts to make white blood cells that are not normal. The leukaemia cells enter your child’s bloodstream and replace healthy white blood cells. This causes:

  • your child to be open to serious infection and illness
  • the blood stops carrying oxygen around the body
  • the blood to stop clotting or thickening to stop bleeding.

Different types of leukaemia will affect different types of white blood cells. They can include:

  • Acute Lymphoblastic Leukaemia (ALL) –most common in children between two and eight 
  • Acute Myeloblastic Leukaemia (AML) –most common in children younger than two and teenagers
  • Chronic myelogenous leukaemia - most common in teenagers 
  • Juvenile myelomonocytic leukaemia (JMML) – most common in infants and toddlers. 

 Signs and symptoms

The symptoms of leukaemia depend on the number and location of leukaemia cells in the blood.

Some children will not have any symptoms. Other children might start to get viruses or bacterial infections more often than other children.

They may also be: 

  • looking very pale
  • feeling very tired or weak
  • getting short of breath while playing 
  • bruising very easily
  • getting a lot of nosebleeds
  • bleeding for a long time after a small cut or graze. 

  Other common symptoms of leukaemia can include: 

  • pain in the bones or joints, sometimes causing your child to limp
  • swollen glands called lymph nodes in places like the neck and groin
  • not wanting to eat
  • sudden weight loss 
  • fever with no other symptoms 
  • belly pain or stomach ache. 

Leukaemia can also cause symptoms in specific areas of the body, depending on where the cells are. For example:

  • the brain – headaches, seizures, problems with balance and vision
  • lymph nodes in the chest – breathing problems and chest pain.

See your local doctor if your child shows any of these symptoms as soon as possible.


Your child’s local doctor will try to rule out any other illnesses first. They will:

  • take a blood test
  • do a physical check to see if your child’s organs feel a bit bigger than normal
  • take a medical and family history.

Your child will be referred to a cancer specialist, called an oncologist.

The oncologist will be able to check symptoms and diagnose leukaemia using:

  • blood tests
  • x-rays of the organs
  • genetic testing to look for changes in genes
  • lumbar puncture – a test to check the fluid around the brain and spinal cord, called the cerebrospinal fluid
  • a bone marrow aspiration and biopsy - a procedure where a sample of the bone marrow liquid and tissue is taken out and tested.


Children with leukaemia will work with a team of health professionals. This team can include:

  • an oncologist
  • nurses
  • social workers
  • psychologists
  • surgeons. 

The main treatment for childhood leukaemia is chemotherapy.

Chemotherapy is a cancer treatment that uses a mix of medicines to kill cancer cells and stop them from growing. The amount and type of chemotherapy drugs used can be different, depending on your child's age and the type of leukaemia they have. 

Other treatments can include: 

  • radiotherapy  - high-energy X-rays used to kill cancer cells 
  • targeted therapy - specific drugs that find and attack cancer cells without hurting normal cells 
  • stem-cell transplants - when donated stem cells are put into the body to replace the leukaemia cells. 


Risk factors for leukaemia

Doctors do not know what causes leukaemia, but some risk factors can make it slightly more likely. 

Risk factors include:

  • being exposed to high levels of radiation, like radiation from an atomic bomb explosion 
  • being exposed to chemicals like benzene, which comes from volcanoes, bushfires, gasoline, and cigarette smoke 
  • previous treatment of cancer with chemotherapy or radiotherapy 
  • certain genetic disorders, like Down syndrome 
  • having a history of other blood disorders 
  • having a family history of leukaemia. 

Having one or more risk factors does not mean your child will develop leukaemia. Many children will have at least one risk factor but will never develop leukaemia, while other children with leukaemia may not have any known risk factors.

Always speak to your local doctor if you are concerned.

Leukaemia remission

Most children with proper medical treatment will have a 90% remission rate. Remission means the doctors cannot find any cancer cells in the body. Permanent remission means your child is cured of the cancer.

Support for families

A cancer diagnosis can leave families and children feeling overwhelmed, scared, anxious, and upset. Practical and emotional support during and after treatment is essential and can come from: 

  • family
  • friends
  • healthcare professionals
  • specialised support services.

Speak to your child’s treatment team for information about support services.

Last updated Tuesday 19th March 2024


This factsheet is provided for general information only. It does not constitute health advice and should not be used to diagnose or treat any health condition.

Please consult with your doctor or other health professional to make sure this information is right for you and/or your child.

The Sydney Children’s Hospitals Network does not accept responsibility for inaccuracies or omissions, the interpretation of the information, or for success or appropriateness of any treatment described in the factsheet.

© Sydney Children’s Hospitals Network 2024