If you’re worried about or know a child who’s been diagnosed with a certain type of leukaemia, we have detailed information on childhood acute lymphoblastic leukaemia (ALL) and childhood acute myeloid leukaemia (AML).

What is childhood leukaemia?

Leukaemia is a type of blood cancer that affects white blood cells and bone marrow.

White blood cells are an important part of your child’s immune system that fight infection, and bone marrow is where blood cells like these are made.

Children with leukaemia have large numbers of abnormal blood cells, usually types of white blood cell, which take over the bone marrow and spill out into the bloodstream. Other areas that might be affected are lymph nodes (glands), spleen, liver, testes, the membranes surrounding the brain and spinal cord, gums and skin.

Find out more about blood, bone marrow and your immune system

Types of childhood leukaemia

Leukaemia is divided into many different types - some which develop faster (acute leukaemias) and others which develop more slowly (chronic leukaemias).

Leukaemia in children is almost always acute, but there are different types which affect different cells. Each type of childhood leukaemia acts differently, and will need to be treated differently.

When you’re looking for information about childhood leukaemia, it really helps to know the proper medical diagnosis so that you can find the right information. We have detailed information on

What causes childhood leukaemia?

You and your family aren’t alone: around 440 children are diagnosed with leukaemia every year in the UK.

One of the most common questions asked by parents is ‘Why did my child get leukaemia?’ There’s nothing you could have done to have prevented your child from developing this condition. It’s not possible to ‘catch’ leukaemia and it can’t be passed from parent to child.

Our researchers are working all the time to find out more about what causes leukaemia in children. At the moment we don’t know what causes childhood leukaemia, although changes which occur by chance in the genes of cells in the bone marrow happen in many cases.

We also know that there are sometimes external factors which can have an impact, like exposure to radiation or chemicals, or having treatment for a different type of cancer.

Find out more about the causes of childhood acute lymphoblastic leukaemia and the causes of childhood acute myeloid leukaemia

Childhood leukaemia and the immune system

The immune system is a network of cells, tissues and organs, which protect the body against infection. It reacts quickly to infections, and neutrophils, other white blood cells and lymphocytes in particular play an important role, circulating in the bloodstream to fight infection.

Find out more about the immune system

The most important organs in the immune system are the spleen and thymus. The spleen can become swollen in some cases of childhood leukaemia.

Leukaemia affects the immune system, damaging the body’s ability to fight infection from bacteria and viruses.

Protecting your child

Your child may be more prone to developing infections and they may be more severe and last longer than usual.

It’s very important to protect your child from infection by keeping them away from anyone with a cold or virus, such as measles or chicken pox.

Your healthcare team will be very experienced in preventing and treating infections and will help you to be on the lookout for signs and symptoms so your child can be treated immediately.

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