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CDC Guidelines for Examining Unusual Patterns of Cancer and Environmental Factors - December 2022


According to the CDC, cancer is a major public health problem worldwide and the second leading cause of death in the United States. There are over 200 types of cancer. 1 in 3 people will have cancer in their lifetime. The latest year for which cancer incidence data are available is 2020. In the United States in 2020, 1,603,844 new cancer cases were reported and 602,347 people died of cancer. For every 100,000 people, 403 new cancer cases were reported and 144 people died of cancer.

Cancer is a group of diseases characterized by the uncontrolled growth and spread of abnormal cells that can result in death if not treated. Although the causes of cancer development are not completely understood, numerous factors are known to increase risk, including many that are potentially modifiable (e.g., tobacco use and excess body weight) and others that are not (e.g., inherited genetic mutations). These risk factors may act simultaneously or in sequence to initiate and/or promote cancer growth.

Oftentimes people expect that there may be a cancer cluster, related to an exposure, when they know of family members, neighbors and/or coworkers that have been diagnosed with cancer. Exposure to chemicals in the outdoors, at home, and at work may add to your chances of getting cancer. People are exposed to small amounts of many chemicals, every day, at levels that are usually too small to cause health problems.

There are some chemicals, known as carcinogens, that can increase the risk of getting cancer. Exposure to a carcinogen does not mean that someone will get cancer. Many factors can affect whether a person exposed to a carcinogen will develop cancer, including the exposure duration and the amount (concentration) of the carcinogen, the individual’s lifestyle, and a person’s genetic background.

Below is a list of organizations and various resource documents that define cancer, its causes, and risk factors; address surveillance and tracking of cancer types; address cancer clusters; provide advice on reducing the risk of cancer; provide guidance; and address what various organizations are doing to help understand and prevent cancer.

General Information and Guidance

Centers for Disease Control National Cancer Institute (NCI) and Prevention (CDC)/Agency for Toxic Substances and Disease Registry (ATSDR)/National Institute for Occupational Safety and Health (NIOSH)

National Cancer Institute (NCI)

Environmental Protection Agency (EPA)
National Toxicology Program (NTP)
International Agency for Research on Cancer (IARC)
American Cancer Society
  Occupational Safety and Health Administration (OSHA)
  Joint Pathology Center
  US Department of Veteran Affairs
World Health Organization (WHO)
  State Resources
  Navy and DHA Public Health Resources
  DHA Armed Forces Health Surveillance Division

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