Question

what causes cancer to kill people?

Answer 1

Cancer is the uncontrolled growth of abnormal cells in the body. Cancer develops when the body's normal control mechanism stops working. Old cells do not die and instead grow out of control, forming new, abnormal cells. These extra cells may form a mass of tissue, called a tumor. Some cancers, such as leukemia, do not form tumors.

Some cancers are caused by things people do or expose themselves to. For example, tobacco use can cause cancer of the lungs, mouth, throat, bladder, kidneys, and many other organs. Of course, not everyone who uses tobacco will get cancer, but it greatly increases a person’s risk. It increases their chance of developing heart and blood vessel disease, too.

Radiation can cause cancer. For instance, people exposed to nuclear fallout have a higher cancer risk than those who were not exposed. Sometimes, radiation treatment for one type of cancer can cause another cancer to grow many years later.

Certain chemicals have been linked to cancer, too. Being exposed to or working with them can increase a person's risk of cancer.