The following information was developed by the American Cancer Society, and is presented on Cancer.Net as part of a collaboration between the American Society of Clinical Oncology (ASCO) and the American Cancer Society. Both organizations have long shared a commitment to empowering people with information about cancer they can trust. Learn more about this collaboration and how it will help advance that goal. Used with permission. © 2022.
Is Cancer Contagious?
A healthy person cannot "catch" cancer from someone who has it. Cancer is not contagious.
Common Questions About Causes of Cancer
Get answers to some of the most common questions people have about cancer causes.
More than 1,000 suspected cancer clusters are reported to state health departments each year. But just what is a cancer cluster?
Determining if Something Is a Carcinogen
Substances and exposures that can lead to cancer are called carcinogens. Learn how possible cancer causes are studied and classified by experts.
Known and Probable Human Carcinogens
Lists of substances and exposures that are known or suspected to cause cancer and information on how different agencies and groups test and classify possible carcinogens.
How to Interpret News About Cancer Causes
How to understand the information you may see and questions you should ask when you see news about something causing cancer.