Leukaemia is the most common childhood cancer, accounting for nearly a third of all cancers in children. It is a cancer of the white blood cells. These cells are involved in fighting infection.

There are two different types of white blood cells – lymphoid cells ( lymphocytes) and myeloid cells. Normally, white blood cells are produced in the bone marrow and then they repair and reproduce themselves in an orderly and controlled way. When a child has leukaemia, this process gets out of control and the cells continue to divide but do not mature as they should do.

Symptoms of leukaemia

Children with leukaemia often have a number of symptoms at diagnosis. These may include:

  • Persistent tiredness or looking very pale

  • Bone pain

  • Unexplained fevers and infections

  • Night sweats

  • Weight loss

  • Unexplained bruising, unusual rashes

  • Excess bleeding, for example nose bleeds.


Acute lymphoblastic leukaemia

Acute lymphoblastic leukaemia (ALL) occurs when an immature type of white blood cell (lymphoblasts) take over the bone marrow stopping normal cells from functioning.

The two main subtypes are:

  • B-cell (87% of cases)

  • T-Cell (13% of cases)

ALL accounts for almost 80% of all childhood leukaemias with around 400 new cases every year in the UK.

It most commonly develops between 2 and 3 years of age and is slightly more common in boys than girls.


Treatment is usually divided into three main parts:

  1. Remission induction: the treatment phase when most of the leukaemia cells are destroyed
  2. Consolidation (intensification): further blocks of treatment to eradicate any remaining disease (minimum residual disease)
  3. Maintenance therapy: this is an extended block of treatment to help prevent cancer from returning (relapse).

The total treatment duration for girls is 2 years, and for boys it is 3 years. This is because on average boys and girls respond in slightly different ways to treatment.

Survival rates of ALL are good at approximately 90% 5 year survival.


Acute myeloid leukaemia (AML)

AML is caused by an overproduction of myeloblasts (a type of white blood cell) and accounts for 15% of childhood leukaemia.

Around 70 children are diagnosed with AML every year in the UK. The treatment for AML is shorter and more intensive than for ALL with the total duration of treatment is around 6 months. Children will usually be admitted to hospital for the full duration of their treatment.

A high proportion of children with AML will achieve remission but up to a quarter of these children will relapse (usually in the three years following treatment) so children with AML will be monitored closely after treatment ends.


Chronic myeloid leukaemia (CML)

 CML is very rare in children, but if it occurs, it is treated using a stem cell transplant.

If you are reading this page, the likelihood is that your child, or a child close to you, has been diagnosed with cancer. If you have any further worries or queries, please discuss them with a member of your child's health care team.



Content reviewed July 2021