"Cancer affects 1 in 3 people in the United States. Chances are that you or someone you know has been affected by cancer. Here is some information to help you better understand what cancer is.

You are made up of trillions of cells that over your lifetime normally grow and divide as needed. When cells are abnormal or get old, they usually die. Cancer starts when something goes wrong in this process. Our cells keep making new cells and the old or abnormal ones don't die when they should. As the cancer cells grow out of control, they can crowd out normal cells. This makes it hard for your body to work the way it should.

For many people, cancer can be treated successfully. In fact, more people than ever before lead full lives after cancer treatment" (Visit What is Cancer, American Cancer Society, for more information).