At a glance
View resources and tools to assist health departments in responding to unusual patterns of cancer and environmental concerns.
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Guidelines
Guidelines for Examining Unusual Patterns of Cancer and Environmental Concerns
CDC/ATSDR guidelines to help health departments as they investigate unusual patterns of cancer in their communities.
Fact sheets
Investigating Cancer Clusters and Unusual Patterns of Cancer: Challenges and Limitations
This document contains answers to frequently asked questions about community-level investigations of unusual patterns of cancer.
Standardized Incidence Ratio (SIR)
This document contains answers to frequently asked questions about the standardized incidence ratio, which is one of the methods used to evaluate unusual patterns of cancer.
Forms
Cancer Inquiry Intake Form
This form is designed to assist state, tribal, local, and territorial (STLT) health departments collect standardized information on inquiries about unusual patterns of cancer and environmental concerns, as described in the CDC/ATSDR’s Guidelines for Examining Unusual Patterns of Cancer and Environmental Concerns.
If you would like to access the form, database templates, and instructions, please email CCGuidelines@cdc.gov.
This form can be used as a decision-making tool to determine whether to continue assessing a report of an unusual pattern of cancer and/or environmental concerns.
General cancer resources
CDC's Division of Cancer Prevention and Control
CDC's National Program of Cancer Registries (NPCR) funds state and territorial cancer registries to collect cancer data to measure progress, drive action, prevent cancers, and improve treatment for all people.
The National Institutes of Health's National Cancer Institute (NCI)
NCI conducts extensive cancer research activities and provides educational materials for the public.
Provides information on cancer (including cancer clusters), research, and services.
The American Cancer Society's The Cancer Atlas is a webpage devoted to human carcinogens identified by the International Agency for Research on Cancer (IARC) Monographs. This provides an alternative, user-friendly viewing of data published by IARC Monographs (see below for more information about IARC Monographs and links to their webpage).
Information on cancer and environmental risk factors or exposures
The Agency for Toxic Substances and Disease Registry's Toxic Substances Portal
Provides information about toxic chemicals and health risks, including cancer.
National Cancer Institute's (NCI) Cancer Cluster Website
Provides general background information on cancer clusters and the available resources related to investigating or researching incidence of cancer. NCI provides specific information on their role in conducting routine surveillance studies of cancer incidence. NCI analyzes variations in cancer trends, including the frequency, distribution, and patterns of cancer in groups of people. These analyses may reveal patterns of cancer in specific populations and identify changes that may warrant investigation. In addition, NCI provides resources that allow users to visualize cancer trends by geographic location.
- NCI Cancer Atlas allows users to create maps of cancer statistics, demographics, and risk factors.
- The joint NCI-CDC State Cancer Profiles website provides interactive maps to visualize cancer statistics by states and counties.
National Institute of Environmental Health Sciences (NIEHS)
Provides information about environment-related diseases and health risks, such as electromagnetic fields and cancer.
- The Report on Carcinogens is produced by NIEHS every other year, this report contains an extensive list of chemicals that cause cancer, as well as many other toxicology reports.
- The Report on Carcinogens Data Exploration Dashboard provides a Tableau dashboard for exploring the NIEHS 15th Report on Carcinogens by substance or cancer type. Contains 256 substances that are known or reasonably anticipated to cause cancer in humans.
International Agency for Research on Cancer (IARC) Monographs
Identifies and evaluates environmental and occupational causes of human cancer. Since 1971, more than 1000 agents have been evaluated.
- The List of Classifications by Cancer Sites includes a table summarizing carcinogenic agents with sufficient or limited evidence in humans by cancer site.
United States Environmental Protection Agency (EPA) Integrated Risk Information System (IRIS)
Supports EPA's mission of protecting human health and the environment by identifying and characterizing the health hazards of chemicals found in the environment. Provides cancer descriptors for each chemical and identifies as one of five designations: carcinogenic to humans, likely to be carcinogenic to humans, suggestive evidence carcinogenic potential, inadequate information to assess carcinogenic potential, or not likely to be carcinogenic to humans.
- The Advanced Search enables users to search by organ/system and yield associated chemical, exposure route, and cancer assessment.
CDC's National Institute for Occupational Safety and Health (NIOSH)
Provides information about exposures in the workplace known or suspected to cause cancer. NIOSH also responds to requests from employers, union representatives, or employees to evaluate potentially hazardous working conditions, including concerns about cancer.
CDC's Reducing Environmental and Occupational Cancer Risks: A Toolkit
Provides scientific evidence, information resources and risk reduction strategies to support state chronic disease programs and state cancer coalitions in addressing cancer risks associated with environmental and occupational agents.
Technical assistance
CDC/ATSDR provides technical assistance to state health departments regarding unusual patterns of cancer by request.
If you work for a state health department and have questions about the guidelines or need assistance, please contact CCGuidelines@cdc.gov.