What is cancer?

The organs and tissues of the body are made up of tiny building blocks called cells. Cancer is a disease of these cells. It’s important to realise that cancer is not a single disease with a single cause and a single type of treatment. There are more than 200 different kinds of cancer|, each with their own names and treatments.

Although cells in different parts of the body may look different and work in different ways, most repair and reproduce themselves in the same way. Normally, cells divide in an orderly and controlled way. If for some reason the process gets out of control, the cells carry on dividing, developing into a lump which is called a tumour. Tumours can be either benign or malignant.

Doctors can tell if a tumour is benign or malignant by examining a small sample of cells under a microscope. This is called a biopsy.

The cells in a benign brain tumour don’t spread into surrounding tissue and so are not cancerous. However, they may continue to grow and may cause a problem by pressing on surrounding brain tissue. A malignant tumour consists of cancer cells which have the ability to spread beyond the original site. If a malignant brain tumour is left untreated, it may spread into, and damage, surrounding brain tissue. Sometimes cells break away from the original tumour and spread to other parts of the brain or spinal cord.