New cells are also made during growth, eg during infancy. Normally, the body regulates the growth of new cells but occasionally abnormal cells are produced. These abnormal cells do not function properly and if they are not destroyed by the body, they may develop and increase rapidly. This is cancer. The abnormal cells may also spread to other parts of the body and multiply there.
Cancer can occur in different parts of the body.
In the UK, the most common cancers in men are lung cancer, prostate cancer and colon cancer. The most common cancers in women are breast cancer, lung cancer and colon cancer. Cancer is the second most common cause of death in the UK - it causes about a quarter of all deaths. Heart disease is more common. Cancer is more common in older people than in younger people.