Secondary brain tumours

This information is about secondary brain tumours. We hope that it will answer any questions that you may have.

If you have any further questions you can ask your doctor or nurse at the hospital where you are having your treatment, or speak to one of CancerBACUP’s Cancer Support Service nurses.

What is a secondary brain tumour?

A secondary brain tumour is a tumour within the brain that has occurred because cancer cells have spread into the brain from a cancer in another part of the body.

Some cancers can spread from their original site. The place in which the cancer first started is known as the primary tumour. When the cancer cells have spread to another part of the body they are referred to as secondaries or metastases.

Cancer cells can break away from the primary tumour and travel through the blood or through the lymphatic system. The lymphatic system is a complex system made up of a network of lymph nodes (or lymph glands) that are found all over the body. The lymph nodes are connected by tiny lymphatic vessels.

Some types of cancer are more likely to spread to the brain. The most likely types to spread to the brain are cancers of the lung, breast, bowel, colon, kidney (renal) and skin (malignant melanoma).

It is usually possible to know if a tumour within the brain is a secondary rather than a new primary of the brain itself, because there is usually a history of some other cancer elsewhere in the body, even from a long time ago.

Also, when the rest of your body is scanned other secondaries may be found in other places – for example, in the liver or in the bones.

If there is more than one tumour in the brain, it is likely that these are secondary tumour growths because cancers which start off in the brain usually remain and enlarge in one place. More than one secondary tumour in the brain is sometimes called multiple brain secondaries.

Occasionally, if there is only one growth in the brain (a solitary brain tumour) and if there has never been a diagnosis of cancer elsewhere in the body, it may be difficult to tell whether the growth is a primary or a secondary one. In such situations, a biopsy will be needed and you will be referred to a neurosurgeon for this.

When the cells from the biopsy are examined under a microscope, they may look like the cells from a cancer from another part of the body. For example, if a lung cancer has spread to the brain, the affected cells would look like lung cells rather than brain cells.

Signs and symptoms

Some of the symptoms for a secondary brain tumour are similar to those for a primary brain tumour.

The most common symptoms are headaches, weakness in areas of the body, changes in behaviour, fits (seizures), symptoms of raised pressure in the brain (known as raised intracranial pressure), nausea and vomiting, confusion and listlessness.

A doctor may suspect a metastatic brain tumour if there has been a previous diagnosis of cancer and you have any of the above symptoms. Sometimes secondaries or metastases are found before the primary cancer has been diagnosed. In some cases, even after numerous tests, it may not be possible to find the original cancer and this is situation is known as a secondary brain tumour from an unknown primary.

Diagnosis

To diagnose a secondary brain tumour the doctor will examine you thoroughly.

A CT scan or an MRI scan can sometimes show the difference between secondary and primary tumours.

CT (computerised tomography) scan 

A CT scan takes a series of x- are fed into a computer to build up a detailed picture of your brain. The test itself is completely painless, but it will mean that you have to lie still for about 10 minutes.

MRI (magnetic resonance imaging) scan 

This test is similar to a CT scan, but uses magnetism instead of x-rays to build up cross-sectional pictures of your brain. During the test you will be asked to lie very still on a couch inside a large metal cylinder that is open at both ends. The whole test may take up to an hour. It can be slightly uncomfortable and some people feel a bit claustrophobic during the scan, which is also very noisy. You will be given earplugs or headphones to wear and you can usually take someone with you into the room to keep you company.

Biopsy 

Occasionally it is necessary to take a biopsy (sample of cells from the tumour) to confirm the diagnosis. The biopsy will then be looked at under a microscope. The biopsy operation is done by a neurosurgeon. Your doctor will discuss with you whether this is necessary in your case, and exactly what the operation involves.

Other tests

Using an opthalmoscope the doctor will look into the back of your eyes. They can see if the nerve at the back of the eye is swollen. This happens because of oedema (swelling of the tissues within the brain), which may occur due to an increase in the amount of fluid in the brain.

The doctor may also do an examination to test the power and feeling in your arms and legs and will test your reflexes.

Treatment

Being told that you have secondary cancer in the brain will be a tremendous shock. It is important to discuss any questions, fears and treatment options with your doctor. It is not usually possible to get rid of a secondary brain tumour completely, but treatment can sometimes shrink the tumour, slow its growth and control symptoms.

Steroids are generally given to help to control symptoms. They can temporarily improve headaches, weakness of the limbs and nausea.

Radiotherapy is the most common treatment, but sometimes chemotherapy may also be given. If chemotherapy is given it has to be a type that is able to cross the membranes that protect the brain and spinal cord (known as the blood brain barrier). In certain cancers which have spread to the brain hormonal therapy or immunotherapy may be used.

In some cases, especially if the scans show that there is only one secondary tumour in the brain, it may be possible to remove it by surgery. You will be referred to a neurosurgeon to see whether it is possible to remove it. Following the operation, radiotherapy treatment may be given to reduce the chances of the tumour returning.

Your feelings

You may find the idea of a secondary cancer affecting your brain extremely frightening. The brain controls the body, and not being in control can be very worrying. You may have many different emotions including anxiety and fear. These are all normal reactions and are part of the process that many people go through in trying to come to terms with their condition. Many people find it helpful to talk things over with their doctor or nurse. Close friends and family members can also offer support..

CancerBACUP has a section on the emotional effects of cancer and how to deal with them. CancerBACUP also has a section on coping with advanced cancer, which discusses the practical and emotional issues that may arise when cancer has spread.

References

This section has been compiled using information from a number of reliable sources including;

• Cancer and Its Management (4th edition). Souhami and Tobias. Oxford Blackwell Scientific Publications, 2003.
• Cancer in the Nervous System (2nd edition). Levin. Oxford University Press, 2002.

For further references, please see the general bibliography.