Breast Cancer Genetics
About one in eight women in the United States develop breast cancer during their lifetime. Breast cancer is one of the most common types of cancer seen in women. Most breast cancers are sporadic, which means that they occur for unknown reasons or by chance.
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)
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.
Hereditary breast cancer can be caused by a change in a gene. One example of hereditary breast cancer is Hereditary Breast and Ovarian Cancer syndrome (HBOC). Hereditary Breast and Ovarian Cancer syndrome is caused by a change in the genes BRCA1 and BRCA2. If someone has a change in BRCA1 or BRCA2, he or she may have higher risks of developing certain cancers, like breast cancer. If you have a change in one of these genes, your doctors will help you make decisions about cancer screening and ways to reduce your cancer risks.
BRCA1 and BRCA2 are not the only genes associated with hereditary breast cancer. If you had testing for BRCA1 and BRCA2 in the past, there may be other genetic tests available.
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. You can find a genetic counselor in your area at www.nsgc.org.
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.