Biopsy for brain tumours

A biopsy means taking a small tissue sample from your brain and looking at it under a microscope. This helps your doctors decide the best treatment for you.

You usually have a biopsy of your brain under general anaesthetic. This means that you will be asleep and won’t feel anything.

Having a biopsy sounds like a frightening procedure, but it is quite safe. Doctors who carry out these tests are very skilled specialists. You can share your concerns with your doctor and cancer nurse specialist. They will be able to tell you what will happen.

Types of brain tumour biopsies

A biopsy is done by a specialist doctor, called neurosurgeon. You usually have it as part of the operation to remove the brain tumour, but you may also have it on its own.

There are different types of biopsies. The difference between them is the way the surgeon does the biopsy. You might have:

  • a biopsy as part of the operation to remove the tumour
  • a needle biopsy
  • an open biopsy 
  • a neuroendoscopy 

You might have a biopsy as part of the operation to remove all or part of the brain tumour. This is called a craniotomy. Your surgeon removes an area of bone from your skull. This gives an opening so that they can remove a sample of tumour. 

Your surgeon makes a small hole in the skull and guides a small needle into the tumour to take a sample. 

For tumours that are very deep inside the brain, or that are widely spread throughout the brain, you may have a guided biopsy. A guided biopsy is guided by a CT scan or MRI scan. The scan helps your doctor move the needle into the right place. 

There are 2 main ways of having a guided needle biopsy.

Neuronavigation – you have markers placed on your head before you have the CT scan or MRI scan. A computer uses the markers to locate the correct position of the tumour.

Stereotactic biopsy – you have a head frame that helps the surgeon guide the needle to the tumour.

You might have an open biopsy if a larger sample is needed or there is a higher risk of bleeding. Your surgeon removes a small area of the bone (skull) to allow easier access to the tumour. This procedure is sometimes called a mini craniotomy.

You might have a neuroendoscopy to take a sample of tissue from or around the fluid filled spaces of the brain (ventricles). Your doctor uses a long tube called endoscope to see inside the brain and take samples of tissue.  

Preparing for your biopsy

You meet your surgical team before your biopsy. They will talk to you about the risks and benefits and ask you to sign a consent form. This is a good time to ask any questions you may have. 

Before your biopsy

You might stay in hospital the night before your procedure.


Take your medicines as normal unless your doctor tells you otherwise. If you take medicines to thin your blood, you might need to stop these before your biopsy. Your doctor will let you know when to stop.


You have some tests. These might include a blood test and a heart trace test (ECG). Your doctor or nurse will explain the tests you need. They are similar in all hospitals but not exactly the same. 

Preventing blood clots

Your nurse might give you stockings to wear while you can’t move around as much as usual afterwards. These are tight stockings that squeeze your feet and legs, helping the blood to circulate better.


Make sure you have a shower or a bath the night before your operation. Your team might give you a special antiseptic cleaning soap to use.

Eating and drinking

You have this test under a general anaesthetic so you can’t eat and drink for a few hours beforehand. Your appointment letter will tell you exactly when to stop eating and drinking.

What happens

You have the biopsy in an operating theatre. Before you go, you put on a hospital gown. Then your nurse takes you to the operating theatre. They put a small tube (cannula) into a vein in the back of your hand. Your anaesthetist gives you the anaesthetic medicine through the cannula. 

After the biopsy, you go to the recovery room for a few hours. 

After your biopsy

You might feel a bit drowsy from the anaesthetic when you wake up. You should be able to eat and drink once you are fully awake.

You go from the recovery area to the ward. Your nurse will keep a close eye on you for the first few hours. Your team asks you questions and gives you instructions to follow to check that you are fully awake. They will shine a light in your eyes to check your pupil reaction.

You have medicines to help with any pain you might have. It's not usually too uncomfortable.

You normally stay overnight in hospital after your biopsy. But some hospitals do biopsies as a day case procedure. 

Going home

Your doctor will let you know when they think you can go home. Everyone takes a different amount of time to recover from a biopsy.


Take any medicines you have been prescribed, exactly as your doctor or pharmacist told you. Your pharmacist can make you a reminder sheet if it would help you. Take your painkillers regularly if they have been prescribed. Speak to your GP or hospital doctor if you find that they aren’t working. They can do a lot to help, like changing the amount or the type of pain killers.


Your neurosurgeon will let you know when it's safe to drive.

Possible risks

A biopsy is a very safe procedure but your nurse will tell you who to contact if you have any problems afterwards. Your doctors will make sure the benefits of having a biopsy outweigh these possible risks.

The possible risks of having a biopsy are:


You may have some bleeding in your brain during or after the biopsy. This is usually a small amount. Your team will check for any signs of bleeding in your brain. 


You may have antibiotics if you have signs of infection such as a high temperature (fever). 

Bruising and swelling

You might have bruising around the area where they put the cannula in and where they take the biopsy.

You may have drugs called steroids before and after the biopsy to help with swelling in your brain. 

Getting your results

You should get your results within 1 or 2 weeks. 

Waiting for results can make you anxious. Ask your doctor or nurse how long it will take to get them. Contact the doctor who arranged the test if you haven’t heard anything after a couple of weeks.

You might have contact details for a specialist nurse who you can contact for information if you need to. It may help to talk to a close friend or relative about how you feel. You may want them to go with you to get the results for support.

For information and support, you can call the Cancer Research UK information nurses on freephone 0808 800 4040. The lines are open from 9am to 5pm, Monday to Friday.

More information

We have more information on tests, treatment and support if you have been diagnosed with a brain or spinal cord tumour.

  • Brain tumours (primary) and brain metastases in adults
    The National Institute for Health and Care Excellence (NICE), July 2018

  • Oxford handbook of clinical medicine (10th edition)
    M Longmore and others
    Oxford University Press, 2017

  • Cancer and its management (7th edition)
    J Tobias and D Hochhauser 
    Blackwell, 2015

  • Brain Tumor Imaging
    K Brindle and others
    Journal of Clinical Oncology, 2017. Vol 35, Number 21, Pages 2432-2438

  • Neuronavigation in the surgical management of brain tumors: current and future trends
    D Orringer, A Golby and F Jolesz
    Expert Review of Medical Devices, 2012. Vol 9, Issue 5, Pages 491-500

Last reviewed: 
21 Apr 2023
Next review due: 
21 Apr 2026

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