Cancer Basics

Start in this section to get answers to some of the basic questions about cancer, such as what it is, what some of the common signs and symptoms are, and how many people it affects.

What Is Cancer?

Get a brief overview of cancer, a group of more than 100 diseases in which cells in a part of the body begin to grow out of control.

Signs and Symptoms of Cancer

Cancer is a group of diseases that can cause different signs or symptoms, depending on where it is in the body. Here you can learn about some of the most common signs and symptoms of cancer.

Questions That People Ask About Cancer

Get answers to some of the most common questions people have about cancer.

Is Cancer Contagious?

Can you "catch" cancer from someone who has it through things like sex, kissing, touching, sharing meals, or breathing the same air? Find out here.

Lifetime Probability of Developing or Dying From Cancer

Some cancers are more common than others. Here you can learn more about a person's chances of being diagnosed or dying from certain types of cancer over his or her lifetime.

Cancer Prevalence

Cancer prevalence is the number of people living with cancer at any point in time. It includes people diagnosed with cancer in the past as well as people recently diagnosed. Learn about the prevalence of different types of cancer here.

Economic Impact of Cancer

Get a quick overview of the financial costs of cancer for society as a whole.

History of Cancer

Here we provide an overview of how people have understood and described cancer throughout history, as well as how the treatment of cancer has evolved.

Cancer 101 [Video]

What causes cancer and why is it so hard to treat? Leading experts provide an overview of cancer, from what goes wrong in a cell's genetic instructions to the latest treatment strategies. Duration 04:56.

Learn About Cancer