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Introduction
Why learn about cancer?
How can I use the Internet?
What is cancer?
What can I do to help myself?
What do I need to know about breast cancer?
What do I need to know about prostate cancer?
What do I need to know about lung cancer?
What do I need to know about colon cancer?
Cancer research -- because lives depend on it.
Where do I go for help?
Let's use what we've learned.
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Cancer Information Service

For the latest, most
accurate cancer
information, call
1-800-4-CANCER,

visit our Web site, or

click below to chat live with an Information Specialist from NCI's LiveHelp service, weekdays 9am-11pm ET, for answers to your questions or help navigating NCI Web sites.

 
What is cancer?

Cancer is a very common illness.
There are more than 100 kinds of cancer.

Your body is made up of many kinds of cells.
To understand cancer, you need to know what happens when cells turn into cancer.

In a healthy person, cells grow normally.
Sometimes your body makes more cells than it needs.
These extra cells grow into something called a tumor.
There are two kinds of tumors.
One kind is called "benign." That means it is not cancer.
The other kind is called "malignant." Malignant tumors are cancer.

Spread the word about cancer--help yourself and others stay healthy.

Do you want to know more about cancer? Click on a Web site below:

  1. Cancer: Questions and Answers (Fact Sheet, National Cancer Institute)
  2. What You Need To Know About™ Cancer - An Overview (National Cancer Institute)
  3. Understanding Cancer Series: Cancer (National Cancer Institute)
  4. Dictionary of Cancer Terms (National Cancer Institute)


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