Tests for childhood acute lymphoblastic leukaemia (ALL)
Your child will need a number of tests if their doctor suspects they have leukaemia. These aren't generally painful. But your child will have to keep still for some time. So, for some types of tests, your child might need to be drowsy (
) or asleep ().
The team caring for your child are used to helping children have these tests. They will do everything they can to prepare them, and you.
Your child might have one or more of the following:
- blood tests
- a bone marrow aspirate and trephine - this is a sample of cells from the bone marrow, and a sample of the bone marrow itself, to see if there are leukaemia cells there
- a spinal fluid test (lumbar puncture)
- a chest x -ray
Blood tests
A blood test is an important test for acute lymphoblastic leukaemia. It can check:
- the number of blood cells, this is often called a blood count, or full blood count
- if any of the cells look like leukaemia cells
- your child’s general health, such as how well their liver and kidneys are working
How do they take blood?
A doctor, nurse or takes a small amount of blood from your child. This is usually from a vein in the back of the hand, the inside of the elbow or wrist area.
Most blood tests are over in a couple of minutes.
The specially trained staff will help your child feel as comfortable as possible. Things that can make it easier for your child include:
Local anaesthetic
Your child might have a before the test. This should mean it’s less painful for your child, although they might still feel the needle go in.
Distraction
Distraction could be singing, counting, watching something on your mobile phone or a DVD.
Sitting with your child
Holding your child while they are having their blood test can make them feel safe and secure. And you can give them a cuddle afterwards if you’re unable to hold them during their test.
After their blood test
Your child can usually eat, drink and play as normal after a blood test.
Bone marrow tests
Your child has this test to check whether there are leukaemia cells in the bone marrow. And what type of leukaemia it is. Bone marrow is spongy tissue and fluid that is inside your bones. It makes your blood cells.
How does your child have a bone marrow test?
A doctor or specialist nurse removes a sample of bone marrow fluid (called a bone marrow aspirate). Or a small piece of bone marrow (called a trephine). Your child might have both tests at the same time.
This sample is usually taken from the back of their hip. Doctors then look at the cells or tissue under a microscope.
Most children usually has this test under general anaesthetic in theatres. Some older children may have it performed under sedation and local anaesthetic.
After the bone marrow test
Your child returns to the children’s ward after the test. Their nurse will look after them closely when they return and take regular measurements such as their:
- heart rate
- breathing rate
- blood pressure
- oxygen levels
- temperature
This is to make sure they are recovering from the sedation or anaesthetic. The nurses on the unit usually check that your child has:
- had something to drink
- had something to eat or some milk
- had a wee
- a clean and dry dressing over the site of the test
A bone marrow biopsy is a safe test. Your child’s doctor or nurse talks with you about any possible problems they might have after it.
Spinal fluid test (lumbar puncture)
A lumbar puncture is a test to check the fluid that circulates around the brain and spinal cord. This is called cerebrospinal fluid or CSF. A lumbar puncture checks for leukaemia cells in the CSF. Using a special needle your child’s doctor, or specialist nurse, takes a sample of the CSF from their lower back.
Your child’s team will talk you through the benefits and risks of having a lumbar puncture. There is a risk of bleeding and infection, but this is very rare.
How does your child have a lumbar puncture?
Most children have a general anaesthetic for this test. But occasionally some older children might be able to have local anaesthetic for their lumbar puncture.
The area where the needle goes in, is numbed with a local anaesthetic. If your child has this test under local anaesthetic they might feel some pressure and a slight soreness when the local anaesthetic needle goes in.
The doctor or nurse puts the lumbar puncture needle in through the skin. If your child has a local anaesthetic they wait for the area to get numb first.
The lumbar puncture needle goes into the small of the back and into the space around the spinal cord.
Once it's in the right place, the fluid drips out into a pot. You also usually have intrathecal chemotherapy at the same time. This is an injection of methotrexate chemotherapy into the spinal fluid. It helps to treat and prevent any cancer cells spreading to the cerebrospinal fluid.
The doctor or nurse takes the needle out and puts a dressing or plaster on your child’s back.
After the lumbar puncture
After the lumbar puncture your child returns to the children's ward. Their nurse will look after them closely when they return and take regular measurements such as their:
- heart rate
- breathing rate
- blood pressure
- oxygen levels
- temperature
This is to make sure they are recovering from the anaesthetic. The nurses also checks that your child has:
- had something to drink
- had something to eat or some milk
- had a wee
- a clean and dry dressing over the site of the test
The area might be a little sore or bruised that lasts for a couple of days.
Your child will need to lie flat for about an hour after the procedure to help prevent headaches and to help ensure the chemotherapy goes to all areas of the .
Let your child’s healthcare team know if they get symptoms such as:
- a severe headache
- being sick
- their eyes are sensitive to bright light
- tingling or numbness in their legs
Your child usually has a bone marrow aspirate and lumber puncture together.
Chest x-ray
X-rays use high energy rays to take pictures of the inside of your body. Chest x-rays can show:
- fluid
- signs of infection
- an enlarged heart
- enlargement of the lymph glands in the chest, where leukaemia cells have collected
How does your child have an x-ray?
There is no special preparation for an x-ray. Your child usually has a chest x-ray standing up against the x-ray machine if they are old enough to stand. They have it lying on the x-ray couch if they are younger or unable to stand.
X-rays are painless and quick. Your child won’t feel or see anything. You are usually able to stay in the room when your child is having their x-ray. You need to wear a lead apron to protect you from the small amount of radiation.
Your child’s specialist makes sure the benefits of having an x-ray outweighs the risks of the small amount of radiation.
After the x-ray
Your child can usually eat, drink and play as normal after a chest x -ray.
Other tests
Your child might have other tests depending on what symptoms they have. These tests might include:
- a CT scan
- an MRI scan
- an ultrasound scan
Your child might have whole genome sequencing test for leukaemia. The aim of this test is to look for changes (mutations) in their . But is can also give other information such as which treatment might work better.
For this test your child’s doctor sends some leukaemia cells from the bone marrow and also either a blood sample or a small amount of skin (skin biopsy). The skin biopsy is usually taken at the same time as their bone marrow test.
Getting your child’s results
You get your child's test results quite quickly usually within 48 hours if not sooner. But some more complex tests such as looking for changes (abnormalities) in your child's can take a couple weeks.
Waiting for test results can be a very worrying time. You might have contact details for a children’s cancer specialist nurse and you can contact them for information if you need to. It can help to talk to a close friend or relative about how you feel.
You can also contact the Cancer Research UK nurses for support on freephone 0808 800 4040. The lines are open from 9am to 5pm, Monday to Friday.
Treatment
Get more information on treating childhood acute lymphoblastic leukaemia
