Childhood Acute Lymphoblastic Leukaemia (C-ALL)

ALL is the most common type of childhood leukaemia, with about 450 to 500 new cases diagnosed in the UK each year.

Children with ALL have an excess number of lymphocytes in their blood. These lymphocytes are abnormal and cannot help the body to defend against infections.

Acute means that the blood cancer comes on quickly and, if not treated, will progress quickly. Lymphoblastic refers to the presence of large number of lymphoblasts which are immature white blood cells (lymphocytes).

What causes childhood ALL?

In most cases, there is no obvious cause of childhood ALL. You cannot catch ALL from someone who has it and your child cannot pass ALL on.

A few cases are associated with inherited genetic syndromes, such as Down syndrome, or some conditions that affect the immune system.

Several things have also been suggested as causes, including:

  • Exposure to high levels of radiation
  • Living near power plants, phone masts or chemicals

However, studies have not confirmed any of these as definitive causes of Childhood ALL.

Signs and symptoms of Childhood ALL

The most common symptoms of childhood ALL are fever (high temperature) and fatigue (excessive tiredness).

Children may also bruise or bleed easily, for example, bleeding from the gums when brushing their teeth.

The liver and/or the spleen may be swollen, which may show as a swollen stomach. Lymph nodes (glands) may be swollen.

Children may have bone or joint pains and, in very young children, the first signs may be a reluctance to walk or to crawl.

To summarise, common symptoms and their causes are:

  • Anaemia – looking pale, breathlessness, easily tired
  • Low white cell count – frequent and persistent infections
  • Low numbers of platelets – bruising and/or bleeding

A child with ALL may not show the typical signs of infection. If you child has any of the following signs or symptoms you should contact their GP or the hospital straight away:

  • Raised temperature, cough or sort throat
  • Confusion or agitation, especially if it comes on suddenly
  • Your children suddenly or rapidly becoming more ill
  • Fast heart beat and/or fast breathing
  • Passing very little or no urine
  • An increase in pain

Diagnosis of Childhood ALL

If ALL is suspected, your child will have a set of tests to confirm the diagnosis.

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 general anaesthetic or sedation in children (although older children may prefer local anaesthetic).

Other tests which may be done include:

  • Cytogenetics – This will look at how your child’s leukaemia cells are different from their normal cells, including whether or not they carry an abnormal gene called BCR-ABL.
  • Immunophenotyping – This will show the exact type of ALL that your child has.
  • Lumbar puncture – A sample of cerebrospinal fluid (CSF) is taken from the spine to see whether there are leukaemia cells in the nervous system. In ALL, 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.

Treatment of Childhood ALL

Childhood ALL is one of the most treatable cancers in children.

In the UK, about nine out of ten children with ALL take part in clinical trials. The purpose of a clinical trial is to improve the outcomes of treatment.


Chemotherapy is the use of anti-cancer (cytotoxic) drugs to destroy cancer cells. It is the main part of treatment for ALL in children. The most common used are:

  • Vincristine
  • Mercaptopurine
  • Methotrexate
  • Daunorubicin
  • Cyclophosphamide
  • Cytarabine
  • Doxorubicin
  • Peg-Asparaginase

As well as cytotoxic drugs, it has been found that steroid are very effective in the treatment of ALL. They are used as artificial versions of the natural substances found in your child’s body.

UKALL 2011 Clinical Trial

This phase 3 trial was closed at the end of 2018, looking at whether some children can safely have a lower treatment amount, and whether other children may benefit from have more intensive treatment.

ALLTogether Clinical Trial

This trial is scheduled to open in 2020.

When the trial opens, you will be given full information, and a chance to ask questions about the trial, before being asked to decide whether your child should take part. If you decide your child should not take part, he or she will receive standard ALL treatment.

Stages of treatment

The exact length of each stage of treatment and the choice and strength of drugs used will vary according to the results of tests, and whether your child is in the trial. Importantly, almost all treatment is delivered as an outpatient.

  • Induction phase – Using a combination of drugs over four weeks, the aim is to reduce the number of abnormal cells to as low as possible. An MRD test will be performed to see how many leukaemia cells are left at a molecular level. This will help plan the next phase of treatment.
  • Consolidation phase – Using fewer drugs and lower doses, this stage lasts between three to ten weeks with the intent of destroying any remaining leukaemia cells.
  • Interim maintenance phase – A period of about two months of less intensive treatment.
  • Delayed intensification – Lasting for seven or eight weeks, this stage aims to ‘mop-up’ any remaining leukaemia cells using stronger treatment.
  • Maintenance phase – This is the longest and gentlest stage of treatment, lasting for two years in girls and three years in boys. This stage is needs to prevent the disease from coming back. This stage of treatment involves oral treatment with methotrexate (weekly) and 6-mercaptopurine (daily), along with vincristine IV chemotherapy every three months and oral steroids along with the vincristine for five days. The oral steroids will be taken every time the patient has the vincristine treatment.
  • CNS treatment – Mainly acting as a preventative treatment, this is normally given during the consolidation stage and may consist of radiation treatment to the head and spine, injection of drugs into the CSF or high doses of anti-leukaemia drugs.

Treatment of relapsed childhood ALL

Almost all children have a good initial response to treatment, with blood counts returning to normal. Unfortunately, in some cases the disease will come back, which is known as a relapse.

When a relapse happens with a child on maintenance treatment, there is a good chance that they will respond well to repeating the initial treatment.

When the relapse happens early in treatment, it tends to not respond to repeating the previous treatment. In this case, one treatment option is a stem cell transplant.

Side effects of Childhood ALL

Unfortunately, treatments do come with some side effects, but your child is unlikely to experience all of them. It is difficult to predict what side effects your child will experience as different people react to treatment in different ways.

Your child’s medical team will be able to answer any questions you might have on any side effects likely to be seen.

Short-term side effects

Short-term side effects can include:

  • Fatigue
  • Nausea (feeling sick) and sickness (being sick)
  • Infections
  • Bleeding, especially from the nose or gums
  • Diarrhoea
  • Sore mouth from inflammation
  • Loss of taste and appetite
  • Organ dysfunction, including the liver, kidney or lungs
  • Hair loss

Long-term side effects

Long-term side effects can include:

  • Fatigue – This can take six to 12 months following treatment for your child to feel back to normal.
  • Loss of fertility – This is incredibly rare with current ALL treatments, but some of the intensive drugs can cause temporary or permanent infertility.
  • Heart damage – Drugs such as anthracyclines can affect the heart. This is normally temporary as doses are limited, but it can lead to long-term problems in some people.
  • Secondary cancers – Chemotherapies which damage DNA are known to cause secondary cancers, the most common being myelodysplastic syndromes (MDS) and leukaemia, mainly acute myeloid leukaemia (AML).

Supportive care

Supportive care includes treatment to prevent infections and to manage them when they happen, as well as treatment to deal with the side effects of ALL treatment. Improvements in supportive care have played a crucial part in improving the survival of children with ALL.


Because both ALL and its treatment affect the body’s ability to produce healthy blood cells, most children with ALL need transfusions of red blood cells and often of platelets. It is not possible to transfuse white blood cells, but it is now possible for your child to have injections of growth factors, which help the body to produce more white cells. This will reduce the frequency and severity of infections.


Much of the supportive care is based on good nursing care, but protecting your child from infection outside the hospital is very important. You will be given information on this and will be shown how to recognise infection, or other complications, and who to contact and what to do.

If your child is at school or a playgroup, then measles and chickenpox are particular risks. The hospital staff will help you to explain to your child’s school or playgroup what precautions are necessary.

Follow up

It is very important that any child who has been treated for ALL should have a follow-up programme in place to watch for late effects and deal with these promptly.


Once your child’s treatment is finished, they will need to have regular check-ups at the hospital. These will be frequent at first, probably every 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 and monitor their growth.

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


The outlook for children with ALL has improved greatly over the last 50 years. At one time, almost all children diagnosed with ALL would die of their disease; now about 90% will live for at least five years.

If you are concerned about your child’s prognosis, you can discuss this with your child’s medical team.

New treatments on the horizon

Most of the improvements in the outcome of childhood ALL have come not from new drugs but from improvements in supportive care and in finding better ways to use existing drugs. One important area of research is into ways to use the patient’s immune system to kill off leukaemia cells. If successful, this approach would cause much less damage to healthy tissues and less severe long-term effects of treatment.

Much of the research on potential new drugs is being carried out in adults with ALL, who have poorer results with standard treatment. If new drugs are developed, it is likely that there will be clinical trials to see if they may be a good option for treatment of children.

Further downloads

We have free patient information available for Childhood ALL 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: March 2019 Review date: March 2022