Guidelines for Investigating Suspected Cancer Clusters and Responding to Community Concerns for more information. Please see theĭSHS Protocol for Responding to Community Cancer Cluster Concerns and the CDC and CSTE 2013 Most cancer cluster investigations include an analysis of the occurrence of new cancer cases in a particular area over time and only answer the question, “Are there more cancer cases occurring in the area or population of concern than would be expected, based on the size and demographic characteristics of that population?” It is important to note that the data and statistical analysis conducted at this step cannot determine if cancers observed in the community are associated with environmental, lifestyle, or other risk factors. While government studies blamed chemicals at the plant for the tumors, industry studies have tended to exonerate any chemicals as the cause. Symptom clusters are defined as two or more concurrent symptoms that are related and may or may not have a common cause. The largest cluster of workplace-related brain tumors happened at this vinyl chloride plant now owned by Dow Chemical in Texas City, Texas. The Centers for Disease Control and Prevention (CDC) and Council of State and Territorial Epidemiologists (CSTE) define a cancer cluster as a greater than expected number of cancer cases that occurs within a group of people in a geographic area over a defined period of time. A cancer cluster is the term used to describe the occurrence of a greater than expected number of cancer cases within a specific population such as a. Cancer patients often experience multiple symptoms, and those symptoms can independently predict changes in patient function, treatment failures, and post-therapeutic outcomes.