These may become cancer cells. These cells grow into groups where other normal cells should be growing. This is called metastasis, and can start a secondary cancer. Anyone can get cancer. Animals get cancer, so do plants.
Cancer is rare in children, more common in middle-aged people and most common in old people.
The chance of getting certain cancers may increase as a person gets older and because of factors such as a person's sex, occupation, health habits, lifestyle and family history. The causes of many cancers are not yet known. Cancer cannot be caught. It is not infectious like a cold or the flu. Most cancers seem to be caused by our lifestyle habits and recreation or by substances in our environment that affect our bodies.