Brain tumours

How cancer develops

About brain tumours

Brain tumours are classed as either primary or secondary.

  • Primary brain tumours develop from normal cells in your brain.
  • Secondary brain tumours develop when cancer cells from other parts of your body, such as your lung or breast, spread to your brain.

This factsheet will focus on primary brain tumours.

Primary brain tumours can be malignant (cancerous) or benign (not cancerous). Each year in the UK, about 5,000 people are diagnosed with a malignant brain tumour and about 4,300 with a benign brain tumour. Brain tumours can occur at any age but are more common in older people. About 300 children are diagnosed with a brain tumour each year. Cancerous brain tumours are the second most common type of childhood cancer after leukaemia.

Types of primary brain tumour

There are many different types of primary brain tumours. They are usually named after the type of brain cell that they develop from, but may also be named after the area of the brain where they are growing. The most common types of primary brain tumours are described below.


More than half of all primary brain tumours are gliomas. They grow from glial cells, which support the nerve cells in your brain. The most common types of gliomas are:

  • astrocytomas and glioblastomas, which grow from cells called astrocytes
  • oligodendrogliomas, which grow from cells called oligodendrocytes
  • ependymomas, which grow from cells called ependymal cells


About one in four brain tumours in adults is a meningioma. These tumours start in the layers of tissue that cover your brain (the meninges) and are usually benign.

Pituitary tumours

About one in 10 brain tumours develops in the pituitary gland. These are called adenomas and are usually benign.


Medulloblastoma is a type of tumour that usually develops in the cerebellum at the back of your brain. It rarely affects adults but is the most common malignant brain tumour in children.

Brain tumour grade

Grading is used to describe how your tumour looks under a microscope, which gives your doctor more information about how it may progress, and so how best to treat it. A low-grade cancer cell looks most similar to a normal cell and will probably grow slowly. A high-grade cancer cell looks abnormal and grows more quickly, and so is more likely to spread. The grades range from one to four, with one being a benign tumour that is the least likely to spread and four being malignant and the most likely to spread.

Symptoms of brain tumours

The exact symptoms you have will depend on many factors, including the size of the tumour and its position in your brain. Some brain tumours don’t cause any symptoms and may only be discovered by chance.

The most common symptoms of brain tumours are headaches and seizures (fits). If you have a headache, it may be worse at night and early in the morning, but wears off as the day goes on. You may also feel sick or vomit and have blurred vision. These symptoms can be caused by increased pressure in your skull from the tumour – this can happen even if your tumour is benign. Although headaches are one of the most common symptoms, it's important to realise that headaches are extremely common and brain tumours are very rare – most headaches aren’t caused by brain tumours.

If your brain tumour causes you to have seizures, you may become unable to speak and have moments of unconsciousness. Alternatively, you may have weakness on one side of your body, difficulties with speaking, reading and writing, problems with hearing or sense of smell and changes in your personality, memory or mental ability. This may be because your brain tumour has grown into particular areas of your brain and is pressing down on them.

These symptoms aren't always caused by a brain tumour but if you have them, see your GP. More common causes of symptoms like this may be migraine headaches or stroke.

Causes of brain tumours

The exact reasons why you may develop a brain tumour aren’t fully understood at present. Most brain tumours are thought to develop from unusual and random changes in your brain cells, but what causes these isn’t known.

There are a number of factors that slightly increase your risk of developing a brain tumour, including:

  • your age – the older you are, the more likely you are to get a brain tumour
  • having an inherited disease – for example, neurofibromatosis (a condition that affects the development and growth of nerve cells)
  • being exposed to high doses of radiation – for example, if you have radiotherapy to your head as treatment for another cancer
  • having a weakened immune system – for instance, if you have HIV/AIDS, or if you take medicines that suppress your immune system

Currently, there is no evidence to show that mobile phones can cause brain tumours.

Diagnosis of brain tumours

Your GP will ask you about your symptoms and examine you. He or she may carry out tests to assess your reflexes, co-ordination, muscle strength, memory and vision.

Your GP may refer you to a neurologist (a doctor who specialises in identifying and medically treating conditions that affect the nervous system) or to a neurosurgeon (a surgeon who specialises in identifying and surgically treating conditions that affect the nervous system).

You may have the following tests to confirm diagnosis and to find out what type of brain tumour you have.

  • Blood tests – these assess your general health and check for specific chemical markers in your blood.
  • CT scan – this uses X-rays to make a three-dimensional image of your brain.
  • MRI scan – this uses magnets and radio waves to produce images of the inside of your brain.

You may need to have a biopsy (where a small sample of tissue is removed) to find out the type and grade of your tumour. Your doctor will use your CT and MRI scans to accurately find the position of the tumour. The biopsy will then be sent to a laboratory for testing. Your treatment will be planned according to the type and grade of brain tumour you have.

Treatment of brain tumours

Because different brain tumours develop in different ways, your treatment will vary depending on which type you have, its size and grade, and position in your brain.

Depending on the type of tumour you have, the doctors and nurses looking after you will discuss your treatment options in more detail and give you further advice and information so you can make a decision about what treatment you wish to have.

You will be treated by a multidisciplinary team including neurologists, neurosurgeons, clinical oncologists (doctors who treat cancer using X-rays and medicines) and specialist nurses who support you through diagnosis and treatment.

Watchful waiting

If your tumour is slow-growing and not causing many symptoms, you may not need any treatment straight away. Your condition will be monitored closely with routine check-ups and scans. This is often called active monitoring or watchful waiting.


The aim of surgery is to get rid of as much of the tumour as possible. Malignant brain tumours can be difficult to remove completely, but your surgeon is still likely to recommend taking out as much of it as possible. This is called a subtotal resection or debulking and is intended to slow down growth and help ease your symptoms.

Depending on the type of brain tumour you have, as well as its size and position, your surgeon may recommend open surgery (craniotomy) or keyhole surgery. If you have a pituitary tumour, your surgeon may advise having it removed via your nose (called transphenoidal surgery).

You will usually be given a general anaesthetic, which means you will be asleep. However, it’s possible that you may need to be awake for the procedure if your surgeon has to assess your brain function during the operation. This is important for removing tumours from areas of your brain that control vital functions such as movement, feeling and speech.

You may need to have chemotherapy or radiotherapy after surgery to make sure that all the cancer cells are destroyed.

Non-surgical treatment


Radiotherapy uses a targeted beam of radiation to destroy your tumour while minimising the damage to the surrounding healthy tissue. Radiotherapy is usually used either after surgery to kill any remaining tumour cells, or as an alternative to surgery. You may have it as a series of daily treatments over two to six weeks or as a single very highly focused treatment called radiosurgery (also known as gamma knife treatment).


Chemotherapy uses medicines to destroy cancer cells. You usually have it as tablets or by injection. Only a few chemotherapy medicines are effective at treating brain tumours – the most commonly used are temozolomide or a combination of three medicines called procarbazine, lomustine (also called CCNU) and vincristine.

Temozolomide tablets are now frequently used in combination with radiotherapy to treat malignant brain tumours called glioblastomas. This treatment may also be used if your tumour comes back.

It’s possible that when your surgeon is removing your tumour, he or she will put small implants (called wafers) that release chemotherapy medicines into the affected area of your brain to kill any remaining tumour cells.


Steroids are hormones (chemicals) that your body makes to help reduce swelling. Synthetic (man-made) steroids can help to reduce swelling that may be caused by your brain tumour, surgery or radiotherapy.

New treatments

New treatments for brain tumours are being tested in clinical trials all the time. Some of these act like chemotherapy medicines and others affect brain tumours in different ways. You may be given these as tablets or injections. It’s possible that you will be able to take part in a clinical trial to test one of these new treatments – speak to your doctor for more information.

Help and support

Being diagnosed with cancer can be distressing for you and your family. Dealing with the emotional aspects, as well as the physical symptoms, is an important part of treatment. Specialist cancer doctors and nurses are experts in providing the support you need. You may also find it helpful to see a counsellor.

Can mobile phones cause brain tumours?


No, there is currently no evidence to show that mobile phones can cause brain tumours.


Mobile phones give out and receive radio waves, which can heat up your body. There are guidelines in place to make sure that none of the mobile phones sold in the UK expose anyone to harmful levels of radio waves.

In 2012, the Health Protection Agency looked at all the research carried out into mobile phones and health. It reported that there still isn’t any convincing evidence to suggest mobile phones will cause you any harm.

However, because mobile phones are a fairly recent invention, researchers can't be absolutely sure that they don't cause any health problems if they are used over a long period of time. For this reason, it's recommended that you try to keep any calls on your mobile phone as short as possible to minimise the amount of radio waves that you're exposed to. Children under the age of 16 should only use mobile phones if it's essential. This is because their brains and nervous systems are still developing, so exposure to radio waves could potentially have a greater effect on them.

Can my brain tumour come back after treatment?


Brain tumours can be treated successfully, but it’s possible that they may come back. This depends on the type and grade of your tumour as well as how much of it has been removed with surgery. You may need to have regular check-ups after you have finished treatment, even if the tumour was benign (non-cancerous) and didn’t spread into other tissues.


Both malignant (cancerous) and benign tumours can come back after they have been treated. When brain tumours come back, they usually grow in the same area of your brain as the first time, but they can also develop in a different area of your brain or sometimes in your spinal cord.

If your brain tumour comes back after treatment, your doctor will look at all the possible options. This will depend on what kind of treatment you had for your first tumour.

You might be able to have surgery to remove the tumour. This will depend on a number of factors including the type and size of the tumour, how quickly it's growing, whether it has spread within your brain or to your spinal cord and also on your general health.

It's usually possible for you to have chemotherapy if your tumour has come back. Even if you have had this treatment before, your doctor may be able to try again, perhaps using a different medicine.

If you had radiotherapy to treat the first tumour, you may not be able to have it again. This is because radiation can cause damage to the healthy tissues in your brain. If the brain tumour is in the same area as the first one, you probably won't be given radiotherapy as it could cause too much damage to the healthy areas (although your surgeon may consider giving targeted radiotherapy). If the tumour has come back in a different part of your brain, it may be possible for you to have more radiotherapy.

If you have already tried all treatment options and your doctors are unable to get rid of the tumour, you can be given treatment to help control your symptoms. You may be given steroids, which will help to relieve your symptoms by reducing the swelling inside your head, and painkillers to help with your headaches. You may also be given anticonvulsant medicines to control or prevent fits, as these sometimes occur in people with advanced brain tumours.

After I have been treated, what will happen at my check-up appointments?


You will need to have regular check-ups after you have been treated. Your doctor may ask you to have a number of different tests, including scans, but this will depend on your condition and what treatment you received.


The type of doctor you have your check-ups with will depend on what kind of treatment you had. The appointments may be with your oncologist (a doctor who specialises in cancer care), surgeon or another specialist.

When you go for your check-up, your doctor may examine you and ask whether you have had any symptoms. You may also need to have a CT or MRI scan, but this is usually only necessary if your doctor thinks the tumour may be coming back. If your brain tumour does come back, you may get similar symptoms to the ones you had with the first tumour. However, these symptoms don't always mean that the brain tumour has come back and could be for many other reasons. You should always tell your doctor about any new symptoms as soon as possible. If your treatment has been successful, as time goes by you may need to have check-ups less frequently.

It's not possible for doctors to predict exactly when or if your brain tumour will come back. Therefore, you will need to have regular check-ups after you have finished treatment, even if the tumour was benign (non-cancerous) and didn’t spread into other tissues.

If I have a brain tumour, can I drive?


As soon as you have been diagnosed with a brain tumour, you will need to stop driving and contact the Driver and Vehicle Licensing Agency (DVLA). They will let you know when it's safe for you to start driving again.


If you have a brain tumour, you're required by law to let the DVLA know. This is because there is a risk of developing epilepsy with a brain tumour, which could affect your vision and therefore your ability to drive. You won't be allowed to drive until the medical department at the DVLA confirms that you're safe to do so. This is for your safety and that of other road users. The DVLA may need to contact your doctor to come to a decision about how long it will be unsafe for you to drive. Once this time has passed you will probably be able to drive again after passing a medical assessment, which will test your sight and how well you can control a vehicle.