About brain tumours
What is a brain tumour?
Tumours are caused by abnormal cell growth. Brain tumours can start in the brain; these are called ‘primary tumours’. If the tumour has spread to the brain from a cancerous tumour in another part of the body, they are called secondary tumours or metastases.
The cause of brain tumours is still very unclear. Recent research has taken place to see if mobile phones, sweeteners or even computers are to blame but so far there have been no clear risk factors. There does not appear to be any links with occupation, head injury or infections. The majority of tumours are not inherited although in a small minority of cases an abnormal gene can be found. If you have a concern about this, please see your doctor.
Several general symptoms may be associated with a brain tumour such as headache, vomiting, seizures, localised twitching, loss of vision or hearing, drowsiness.
A growing tumour can cause pressure either from the tumour itself or by blocking the flow of the cerebrospinal fluid which normally flows in and around the brain.
However, a brain tumour will cause different symptoms depending on where the tumour is situated. Brain stem tumours can cause difficulty with swallowing, speaking and tongue movements while tumours in the occipital part of the brain will cause disturbance with vision.
Types of tumours
Brain tumours can be grouped according to the type of cell they arise in.
The main types of tumour are:
Glioma affecting the glial cells and are the ‘scaffolding’ in the brain which binds the nerve cells and fibres together.
Meningioma affecting the meninges which are the membranes that cover the brain.
Haemangioma tumours of the blood vessels in the brain
Pituitary adenoma tumours of the pituitary glands
Not all tumours are cancerous or malignant but even benign tumours can be life threatening due to their position in the brain. Pressure that builds up in the head can cause damage to the brain. Almost half of all brain tumours are benign and can successfully removed by surgery.
Your Doctor will refer you to your local hospital or special neuro-science unit for more investigations.
These will consist of an MRI scan or a CT scan (to give a picture of inside the head) and some neurological tests to assess things like balance, sight and strength (functions like these may be affected if a tumour or lesion is in the brain).
If any abnormalities are found, you will then see a neurologist or a neurosurgeon to discuss any treatment.
The aim of surgery is to remove as much of the tumour as possible.
Radiotherapy is a treatment using radiation to bombard the cancerous cells. It is often used following surgery mostly for the treatment of malignant tumours although it can occasionally be used to treat benign tumours
Chemotherapy is the use of drugs to destroy tumour cells in the same way that antibiotics kill bacteria.
Some people do not want medical information. Others find it very helpful. The following information explains a little about the background of brain tumours and their treatment. Always ask a member of the hospital staff if you do not understand anything.
Our brain and spinal cord are partners and they control the work of our bodies by sending messages along nerves or by regulating the release of hormones. A hormone is a chemical substance which is made in one organ and carried by the blood to another where it will have a particular effect. Our brain and spinal cord together are called the central nervous system.
The central nervous system has four main parts. The cerebrum is the largest part of the brain. It is divided into two halves, called the right hemisphere and the left hemisphere. Each hemisphere has four separate parts called lobes. There are the frontal lobe, the parietal lobe, the temporal lobe and the occipital lobe. Lobes do the following jobs to help us in our daily lives.
The frontal lobe controls memory, speech, personality, bladder control, and limb movement
The parietal lobe controls reading, writing, speech, movement and sensation
The occipital lobe controls vision
The temporal lobe controls balance, verbal and visual memory, speech and hearing
All this may sound very complicated; and, to add to the complication - the left half of our brain controls the right side of our body, and the right half of our brain controls the left side of our bodies!
The cerebellum is the next largest section of our brain. It is needed for our balance, posture, co-ordination of muscular movements, walking and speech.
The brain stem is a part of the brain in front of the cerebellum. It controls our basic functions which are not under our own control such as our blood pressure, heart beat and breathing. It also controls sensation, the movements of our head, mouth, face and eyes, and our swallowing.
The spinal cord contains nerves which send messages from our brain to our muscles and other structures in our bodies. It also takes messages from various parts of our bodies back to our brain.
The brain and spinal cord are protected by our skull and by our backbones (called vertebral column). There is also a special fluid produced by the cells in our brains. It is made in channels called ventricles and it flows over the surface of the brain and spinal cord, to provide nourishment and support. This fluid is called cerebro-spinal fluid.
Cells and cancer
Our bodies are made up of tiny structures called cells, which are not visible to the naked eye. Groups of cells form the tissues and organs of our bodies, for example our brain, liver, kidneys and lungs. Each organ has a particular job in making our bodies function properly.
Our cells reproduce themselves by dividing in a regular orderly fashion so that growth and repair of the body tissues can take place. However, this normal function of our cells sometimes goes wrong and there is an uncontrolled growth of cells which causes a swelling or lump. Tumour is the word used to describe the lump.
Benign tumours stay in one place and can be treated perhaps by surgery, and will probably not cause any more problems. A wart is one example of a benign tumour.
However, some tumours are not benign. They may occur in various parts of our bodies and cause trouble for us. These types of tumours are called malignant or cancer. Cancer is a word used to describe many different diseases which have different causes and which are treated in different ways. All cancers are treatable but not all are curable.
Some symptoms of brain tumours
People’s symptoms will vary according to which part of the brain that the tumour is in. Your sight may be affected so that you see only half or a quarter of the total picture. Sometimes your vision may be blurred. Occasionally things can be seen twice, this is called double vision.
Sometimes a person may get a weak arm or leg. This usually happens on the same side of the body. It is a little bit like a ‘stroke’. Sensations may also change. Walking may feel strange, as if you are walking on cotton wool. Sometimes it may be difficult to recognise changes in temperature or if you have a pain. These symptoms are not because something has gone wrong with your leg or arm or feelings, but because the tumour and the pressure around it are interfering with the messages coming from the brain to the rest of your body.
When messages pass along brain cells an impulse is created, like an electric current. This is normal, but any damage to brain cells caused by a tumour or an injury, can create abnormal impulses and these may cause an epileptic fit. Another name for this is seizure. A seizure can take various forms. You may shake or feel a change in sensation in half of your body or in one limb or in one side of the face. A seizure is usually followed by feelings of tiredness and sleepiness. It may take just a few seconds or several minutes to recover from it. The seizure may start with an unusual sensation of smell, taste or sound. This is called an aura. An aura is a warning signal. It can help you to be ready for the seizure, and give you time to sit down in a safe and comfy position, and call somebody to help you. It is best to relax if you feel a seizure coming on, and make sure you are not standing at the top of the stairs or beside something sharp or hot.
Tumours in those areas of the brain which control speech may cause some difficulties in reading, writing, talking or understanding speech. Raised intracranial pressure may give you a headache. The headache may make you feel sick or even be sick.
Remember that the doctors and nurses will do everything they can to help and advise you with these problems.
Understanding and coping with epilepsy
Epilepsy is not a psychiatric illness, but is due to a temporary disruption of electrochemical activity in the brain. Epilepsy can occur in individuals diagnosed with a brain tumour and can manifest itself in what is commonly known as “fits”. These fits or seizures can range in severity from simple to prolonged, which may lead to loss of consciousness. Seizures are not usually dangerous, but they can be very frightening and upsetting for those who have not seen or experienced one.
There are two main types of seizures
Generalised seizures, when the whole brain is affected
Partial seizures, which affect part of the brain
These two types are further divided into simple and complex depending on whether the person loses consciousness.
In simple partial seizures, consciousness is not affected but there may be a wide range of involuntary motor movements, such as a twitch of one side of the face or of an arm or of a leg, which may last from seconds to a couple of minutes.
In complex partial seizures, there is temporary impairment of consciousness. You may experience strange sensations such as visual and auditory hallucinations, that is seeing or hearing something which is not actually there. Some people report that they experience strange smells.
Those people experiencing generalised seizures may experience tonic clonic seizures or absence seizures. Previously known as grand mal fits, tonic clonic seizures involve stiffening of the body, followed by falling, and rhythmic convulsive jerking movements of the muscles. Feelings of drowsiness and disorientation may last for several hours.
In absence seizures, previously known as petit mal, the person simply looks blank and stares, occasionally blinking or twitching. At times, this type of seizure can be mistaken for daydreaming. The type of seizures, you may experience, if any, depend on the site of the tumour in the brain.
If you are aware of the onset of a seizure, sit down and make yourself comfortable and wait for the fit to pass. If you experience “tonic clonic seizures”, instruct your relatives to make sure you are lying on your side and to place a folded blanket or towel under your head to prevent injury. You must also tell them, that under no circumstances, should they place any instruments or their fingers in your mouth. It is important to refrain from activities, which could be dangerous, such as climbing or swimming, without proper supervision. In the United Kingdom, there are driving restrictions, which are imposed by the Driving and Vehicle Licensing Authority (DVLA). You have a legal obligation to inform the DVLA about your epilepsy. Remember with appropriate medication, those with brain tumours, who experience epilepsy, are generally kept seizure free. So always take your tablets as instructed and discuss any problems with your doctor or nurse.
For further information, please contact,
The National Society for Epilepsy
Chalfont St Peter
Tel : 01494 601300