Cancer is a term used for diseases in which abnormal cells divide without control and can invade other tissues. It is a genetic disease—that is, it is caused by changes to genes that control the way our cells function, especially how they grow and divide.
Cancer cells can spread to other parts of the body through the blood and lymph systems. It can start almost anywhere in the human body, which is made up of trillions of cells.
Common Causes of Cancer
Learn about some of the most common causes of cancer, and what you can do to lower your exposure or risk.