Gastrointestinal Cancer Genetic Counseling
The gastrointestinal system is also known as the digestive system. The digestive system has several parts including the stomach, small intestine, colon, and rectum. Colon cancer is one of the most common cancers diagnosed in the United States. The lifetime risk for someone in the general population to develop colon cancer is about 5%. Often, colon cancer develops from polyps in the colon that can be found by routine colonoscopy screening.
Genetic counselors look for these patterns to determine if cancer could be hereditary. "Hereditary" means that there could be a genetic cause for the cancer in the family. When we think about genetics, we are talking about DNA. DNA is the instruction book for our body. Just like a book, DNA can be broken down into chapters, sentences, and letters. Genes are the sentences of DNA.
When you think about your family, are there many people who have had cancer? If there is a strong history of cancer in your family, you may wish to meet with a genetic counselor.
Some of the patterns that genetic counselors look for in a family history include:
- Two or more close relatives with cancer
- Cancer diagnosed before age 50
- More than one diagnosis of cancer in an individual (second primary)
- Several generations with cancer
- Unusual or rare cancers
- Ethnicity (for example, Ashkenazi Jewish)
Sometimes colon cancer can be hereditary. A condition called Lynch syndrome causes increased risks to develop colon and stomach cancers. Lynch syndrome is caused by a change in one of five genes: MLH1, MSH2, MSH6, PMS2, and EPCAM. If someone has a change in one of the Lynch syndrome genes, they may have increased risks to develop certain types of cancers, including colon cancer. If you have a change in one of these genes, there are cancer screening options, ways to reduce your cancer risks, and recommendations for your family.
There are also hereditary cancer syndromes that cause the development of hundreds of colon polyps. One of these syndromes is called Familial Adenomatous Polyposis, or FAP. Individuals with FAP can develop hundreds to thousands of colon polyps, and have high risks to develop colon cancer. FAP is a rare condition. If you or a family member have been found to have numerous polyps during a colonoscopy, you may wish to talk to your doctor about meeting with a genetic counselor.
What is Genetic Counseling?
Genetic counseling is the process of helping people understand and adapt to the medical concerns in their family. Genetic counselors help people make informed decisions about their health and genetic information.
Genetic counselors work in a variety of areas including pregnancy care and planning, pediatrics, cancer, and others. Genetic counseling is specific to your needs and the information you are seeking. Carle Cancer Center offers genetic counseling services. Your team can work with you to set up an appointment.
How to Prepare for Your Cancer Genetic Counseling Appointment
A typical genetic counseling visit includes:
- Discussion of medical history
- Collection of family history
- Discussion of how cancer risks can be passed down in a family
- Discussion of cancer prevention options and screening
- Review of genetic testing options
- Provide supportive counseling
People who have genetic counseling may have one visit, while other people meet with a genetic counselor every few years. Since information about cancer genetics is growing, and new testing options or recommendations may become available, you may wish to follow-up with a genetic counselor even if you had genetic counseling in the past.
You may want to gather some information before meeting with a genetic counselor. You may not be able to get all of the details, but the more information you have, the more your genetic counselor can help.
- Ask your relatives about medical conditions in the family, especially if someone has had cancer. How old were they when the cancer was diagnosed? Has anyone had genetic testing in the family?
- Gather any medical records of your cancer history or family history, especially if testing, diagnosis, or treatment were not performed at Carle Foundation Hospital.
- Bring a list of questions to your appointment.