About Cancer

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Science-based information you can trust

After a Diagnosis

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Knowing what to expect can help you approach your diagnosis with confidence or support a loved one with cancer.


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Understanding your treatment options, including clinical trials, can help you make informed decisions and feel more in control.

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Build Your Quit Plan

Use NCI's Smokefree.gov tools and resources to create a plan to quit smoking or vaping.

Get Started
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Contact Us for Help

NCI offers free information on cancer topics in English and Spanish. Get live help at 1-800-4-CANCER.

Learn More

Causes of Cancer: What is Cancer? Video Series