Tests for a brain tumour

Your child will need a number of tests if their doctor suspects they have a brain tumour. These shouldn’t be painful. But, your child will have to keep still for some of them.

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.

Tests

For some types of test, your child might need sedation or a general anaesthetic. Tests for a brain tumour might include:

Blood tests can:

  • check your child’s general health, including how well their liver and kidneys are working
  • check the numbers of blood cells
How do they take blood?

A doctor, nurse or person specialising in taking blood (a phlebotomist) takes a small amount of blood from your child. This is usually from the back of the hand, the inside of the elbow or wrist area.

Most blood tests take 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

The phlebotomist might use a local anaesthetic. This means that they apply a numbing spray or cream to your child's skin before they do 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. 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.

Hormones and tumour markers

Tumour markers are substances that either the tumour or your body produces as a response to a cancer. They’re usually proteins. They can be found in the blood, urine or tissue in the body.

Some tumour markers are only produced by one type of cancer. Others can be made by several types. Some markers are found in non cancerous conditions as well as cancer. Doctors might use tumour markers to help diagnose a brain tumour in children.

Some tumours may change the level of particular hormones and your child’s doctor will check for these.
 

CT stands for computed tomography. A CT scan uses x-rays and a computer to create detailed pictures of the inside of your body. It takes pictures of the body from different angles. A computer then puts them together to give a series of pictures. It can help doctors find out if there is a tumour and where it is. It can’t show exactly what type of tumour it is.

How

Your child might have an injection of contrast medium (a type of dye) through a small thin tube (cannula) in their hand or arm.

Many young children have a medicine to make them feel sleepy and relaxed (sedative). This helps them to lie still on the couch for the scan. The couch slowly slides backwards and forwards through the hole of the scanner. The machine takes pictures as it moves.

The scan itself is painless. Your specialist team will let you know how:

  • to help your child prepare
  • long your child needs to not eat or drink before their sedation
  • long the scan is likely to be
After

Your child stays on the day unit or the children's ward for a couple of hours after the scan. This is so the team can be sure they have recovered and are awake enough from the sedation. 

The nurses on the unit usually check that your child has:

  • had something to drink
  • had something to eat or has drunk some milk
  • had a wee

This can help the nurses see if your child has recovered from the sedative drugs.

MRI stands for magnetic resonance imaging. An MRI scan creates pictures using magnetism and radio waves.

Photograph of a child having an MRI scan
How

It produces pictures from angles all around the body and shows up soft tissues very clearly. It can help doctors find out if there is a tumour and where it is. It can’t show exactly what type of tumour it is. This type of scan can also measure blood flow in the part of body being scanned.

Many young children have a sedative or general anaesthetic to help them lie still on the couch for the scan. Most MRI scans involve around 30 minutes of lying still. Your child might have an injection of a special dye before or during the scan to help make the pictures clearer. 

After

Your child stays on the day unit or children's ward for a couple of hours after the scan. This is so the team can be sure they have recovered and are awake enough from the sedation. 

The nurses on the unit usually check that your child has:

  • had something to drink
  • had something to eat or has drunk some milk
  • had a wee

This can help the nurses see if your child has recovered from the sedative drugs.

Testing your nervous system is called a neurological examination. Your child’s doctor might:

  • test your child’s muscle strength by them squeezing the doctor's hands or pushing against the doctor’s hands with their feet
  • look to see if they have any numbness anywhere in their body
  • tap their knee with a small rubber hammer to check their reflexes
  • look into the back of your child’s eyes to see if there are any changes
  • see how your child follows commands – they might see how well they are reading or writing if your child is able

There is usually no preparation for these tests.

Your child can usually eat, drink and play normally after having a neurological examination.
 

A lumbar puncture is a test to check the fluid that circulates round the brain and spinal cord. This is called cerebrospinal fluid or CSF. A lumbar puncture can check for cancer cells or for infection in the CSF. Using a needle your child’s doctor, or specialist nurse, takes a sample of the CSF from their lower back.

Diagram of a childs Lumbar Puncture
How does your child have a lumbar puncture?

Most children have a general anaesthetic Open a glossary item for this test. But occasionally some older children might be able to have a local anaesthetic Open a glossary item for their lumbar puncture. They then have an injection of anaesthetic into the area on the lower back. 

When the area is numb, the doctor or nurse puts the lumbar puncture needle in through the skin. It goes into the small of the back and into the space around the spinal cord. If your child has a local anaesthetic they might feel some pressure and a slight soreness when the needle goes in.

Once it's in the right place, the fluid drips out into a pot. This only takes a few seconds. The doctor or nurse takes the needle out and puts a dressing or plaster on your child’s back.

After a lumbar puncture

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.

You should contact your hospital if your child is at home after a lumbar puncture and they get symptoms such as:

  • a severe headache
  • being sick
  • their eyes are sensitive to bright light
  • tingling or numbness in their legs

Your nurse will tell you what symptoms to look out for and who to contact if you have any problems at home.

It’s likely your child can go home the same day, unless they are staying in hospital for other tests.
 

Your child’s doctor might want to take a sample of a tumour seen on a scan. This is called a biopsy. A specialist doctor called a pathologist looks at the cells down a microscope to find out exactly what type of brain tumour it is. This is so they can be sure what treatment is best.

Not every child has a biopsy, it might be safer for them to have surgery to remove the tumour straight away. This means the doctors find out the type of brain tumour it is after surgery. Or, the tumour might be in an area of the brain that’s difficult to biopsy.

How

Your child has general anaesthetic for this test. This means they are asleep and can’t feel anything during the test.

Your child’s surgeon carefully drills a small hole in your child’s skull, puts a needle into the hole and removes a small piece of the brain tumour.  This might sound quite frightening. But the team consider the benefits and the risks of the procedure before suggesting a biopsy.

Your child’s brain surgical biopsy is done by a specialist surgeon, called a paediatric neurosurgeon. There are different types of surgical biopsy. The difference between them is the way the surgeon does the biopsy.

After

Your child usually stays on the children’s ward for a night after the biopsy. This is so the team can be sure that they are awake enough from the anaesthetic. The nurses on the unit usually check that your child has:

  • had something to drink
  • had something to eat or drunk some milk
  • had a wee
  • a clean and dry dressing over the site of the test

A biopsy is a safe test. Your child’s doctor goes through the risks and benefits with you. The most common risks are bleeding from the site or infection. Your team gives you a telephone number to call if you have any problems at home. If in doubt, give them a call.

Scans for infants

Your doctor might suggest you give your baby a feed as normal and then wrap them in a soft towel or blanket. This can help your baby lie still for their CT or MRI scan.

Babies that have had a feed and wrap scan don't need the same level of monitoring after. This is because they haven't had any medicine to make them feel sleepy.

Last reviewed: 
13 Mar 2019
  • Cancer in children and young people
    F Gibson and L Soanes (Editors)
    Wiley, 2008

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