Medical Overview

Some people do not want medical information. Others find it very helpful. The following pages explain 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.

The Brain

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.