CORE Family Studies

Seattle Colon Cancer Family Registry Cohort

Participant Information

From 1997 until 2011, we recruited people affected by colorectal cancer as well as some of their family members, collecting information that makes up the Seattle Colon Cancer Family Registry Cohort (CCFRC) data. We also interviewed a randomly-selected sample of people not affected by colon cancer, for study comparison. There are four components to our interactions with participants.

Participant Interviews

Our interviewers conduct detailed initial interviews with participants that cover many areas:

  • Family history, including incidences of cancer
  • Personal demographic and medical history (including reproductive and cancer history)
  • Diet
  • Exercise
  • Medications
  • History of cancer screenings

Interviewers then re-contact participants for shorter interviews, to update records on their health. These follow-up surveys occur four to six years after the previous interview. Most people have completed at least two follow-up interviews.These survey questions help scientists identify environmental factors that may influence the development of colorectal cancer.

The answers may point to potential lifestyle changes that help prevent cancer.

Biospecimens and Medical Records

Our interviewers also ask participants for:

  • A donation of biological specimens, such as blood, tissue or saliva samples
  • Permission to view medical records related to cancer screenings and treatment (colonoscopy records, pathology reports, and genetic testing done by outside facilities).

These questions help scientists identify inherited factors that may contribute to the development of colorectal cancer.

The answers may point to cancer screening suggestions that could be more effective in people with a higher cancer risk. The answers may also indicate possible differences in in the effects of cancer treatment, on a molecular level.

Genetic Testing and Counseling

Our registry cohort also includes information gathered from people who have received genetic testing. Some were referred to us by outside genetic counseling clinics; these people also may have had genetic testing done prior to their CCFRC participation. Others were current participants whose backgrounds led us to offer testing and consultation with our staff genetic counselor.

These counseling sessions were important because genetic testing results may have a considerable impact on the client, immediately and in the future. Genetic counseling helps people interpret, understand and adjust to the possibility of having an inherited, high risk of colorectal cancer.

In addition to the main CCFRC interview, we conducted three additional interviews with this group:

  • A baseline genetic counseling interview
  • A two-month follow-up interview
  • A 12-month follow-up interview

Genetic counseling is separate from genetic testing; essentially, the first is a discussion, while the second involves laboratory-based examinations. Also, counseling does not always lead to testing. A genetic counselor may advise differently, based on the client’s personal and family history.

If you would like to find our more about genetic risk assessment and counseling in general, please visit the National Cancer Institute's Cancer Genetics Risk Assessment and Counseling.

Why We Do What We Do

When we follow up with a large group of participants – for years or even decades –scientists learn a great deal about:

  • how cancer impacts an individual, including on a molecular level
  • how and when cancer occurs in families
  • how and when cancer occurs in large populations.

For the reasons above, we continue to collect information on our participants, even if their health remains the same as at the last time we contacted them.

The Seattle CCFRC also shares general, non-identifiable data with other researchers. They can use information we have already collected, to investigate scientific questions which can only be understood by observing conditions that take years to develop.