What is Cancer?
Cancer is a group of diseases that begin in cells, the body's basic unit of life. To understand cancer, it is useful to know what happens when the normal cell becomes cancerous.
The body is made up of many types of cells. Normally, cells grow and then divide to produce more cells when your body needs them. This process helps keep the body healthy.
Sometimes these cells keep dividing when the new cells are not needed. These extra cells form a mass of tissue which is called a growth or tumour.