Cancer Clusters

Aerial view of a suburban neighborhood
Cancer Cluster Guidelines Update - Public Comment Period Open

Now open for public comment: Draft CDC Guidelines for Examining Unusual Patterns of Cancer and Environmental Concerns. Comments will be accepted until July 25.

A cancer cluster is defined as a greater-than-expected number of cancer cases that occurs within a group of people in a geographic area over a period of time. Check out About Cancer Clusters to learn more.

Local or state health departments, along with cancer registries, respond to cancer cluster questions and have the most current local data. If you suspect a cancer cluster in your community or workplace, or if you’d like information such as cancer statistics or trends in your area, first contact your local or state health department or state cancer registry.

When people contact CDC with concerns about a suspected cancer cluster, CDC provides general information about cancer clusters and refers them to the appropriate local or state health department or cancer registry. CDC also provides technical advice to states as requested and develops guidance for state, territorial, local, and tribal health departments on how to respond to cancer cluster concerns.


2013 Cancer Cluster Guidelines

  • This report provides guidelines from CDC and the Council of State and Territorial Epidemiologists for investigating suspected cancer clusters in a residential or community setting.

Cancer Cluster Communication Toolkitexternal icon

  • This toolkit provides resources for public health communicators in particular and the public health community in general when dealing with reports of suspected cancer clusters in a residential or community setting.

Additional Resources

  • This page provides links to useful information about cancer clusters.
Page last reviewed: May 25, 2022