Cancer Investigation Process

The Michigan Department of Health and Human Services (MDHHS) Cancer Investigation Program, together with your local health department and other state agencies, identifies and investigates unusual patterns of cancer, which may be linked to environmental exposures. The Cancer Investigation Program has a variety of resources to assess potential cancer clusters and unusual patterns of cancer. The primary tools used are:

• Utilizing cancer data. Epidemiologists are scientists who study the patterns, causes and control of disease in groups of people. Epidemiologists can use data collected by the Michigan Cancer Surveillance Program to compare the rate of cancer in a particular geographic area to the rest of the county and state. This type of comparison helps us know if the number of cancer cases is higher than expected.
• Working with toxicologists. Toxicologists are scientists who evaluate potential risks of various exposures and the safety of humans, animals and the environment. Toxicologists assist the Cancer Investigation Program with identifying potential environmental exposures in a particular geographic area. They are also available to answer questions about environmental contaminants and testing.

If you have concerns or questions about how things in the environment could affect cancer risk, you can contact the Cancer Investigation Program.

You can reach the Cancer Investigation Program by calling the MDHHS Environmental Health hotline at 800-648-6942 or by emailing Katie Patterson, a cancer epidemiologist, at PattersonK9@michigan.gov. Include a brief summary of your concern and your contact information (for example, your name, email and phone number).

After you contact the Cancer Investigation Program:

1. A cancer epidemiologist will schedule a call with you. An in-depth conversation is the best way to get the information needed to understand your concerns.
2. Discussion about the concern. During the scheduled call, a cancer epidemiologist will ask you about your concerns, including:
• Details about individuals with cancer, like cancer type or year of diagnosis.
• Where cancer has been taking place (for example, schools, neighborhoods or work).
• Any environmental concerns.
3. If appropriate, the epidemiologist may refer your concern to one of our toxicologists to answer more of your questions.

The Cancer Investigation Program will share information with you, which may include:

• General information on reported cancer(s), such as rates over time, potential risk factors and screening and prevention information.   
• Information about any potential environmental contamination sources.
• Publicly available cancer data.
• In some cases, data analysis results from the Michigan Cancer Surveillance Program. The cancer epidemiologist will evaluate this possibility after learning more about your concern.

Detecting potential cancer clusters can be challenging. Some examples of challenges or limitations during cancer investigations include:

• Small sample size: The sample size is the number of cases in an area of analysis. When a sample size is very low, it can limit or prevent statistical analysis. 
• Long latency period: The latency period is the time between exposure and cancer symptoms or a diagnosis. Latency periods vary by cancer type. Cancer could be from an exposure that occurred a long time ago - sometimes decades. 
• Migration in or out of area: The Michigan Cancer Surveillance Program (MCSP) collects a person’s place of residence at the time of their cancer diagnosis. This may not be where they lived in the past or during the time when exposure to a cancer-causing agent happened. 
• Multiple cancer causes: It is very challenging to determine what caused someone's cancer. There could be many different causes and factors over the course of someone’s life that impact their cancer risk. Our program may determine whether cancer is higher or lower in an area, but this might not be related to or caused by environmental contaminant exposures. 
• Surveillance data: The Cancer Investigation Program uses surveillance data collected by the MCSP. The data captures most cancer cases diagnosed in Michigan. 
  • Lag time. Cancer data are often delayed by two to three years. This means recently diagnosed cases may not be included in the datasets used for analysis.
  • Incomplete risk factor information. The MCSP data doesn’t always include information on a cancer’s risk factors. Research studies are designed to study the relationship between risk factors and cancer. For this reason, research studies are rarely performed by MDHHS for cancer investigations.