Ever since Angelina Jolie announced that she’d undergone a double mastectomy after learning she carried the BRCA1 gene, a gene that increased a woman’s risk of developing breast and ovarian cancer, there’s been increased publicity surrounding the role of genetics in cancer.
But who should consider genetic testing? And what exactly can the tests tell you? Kathryn Mraz, MS, CGC, certified genetic counselor with the Cancer Risk Genetics Program at the Memorial Hermann Cancer Center-Texas Medical Center and McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), answers some of the most common questions.
1. How much of a role does genetics play in the development of breast cancer?
While there’s been a lot of talk about genetics and cancer, only about five to ten percent of people who develop breast cancer actually have an inherited genetic component. An additional 10 to 20 percent of people have a familial contribution to their breast cancer risk. That means while we don’t know about a specific genetic finding through testing, their family history still suggests an increased risk for close relatives. This is minimally due to a combination of unknown gene(s) and environmental factors that can be responsible for a pattern of similar cancer(s) in a family. However, the majority of cancer cases are what we call ‘sporadic,’ meaning it just develops by chance.
2. What does genetic testing look for when it comes to breast cancer?
There are three big groups of genes we look for:
- High-Risk Genes: BRCA1 and BRCA2
- Moderate-to High-Risk Genes: ATM and PALB2
- Moderate-Risk Genes: 12 additional genes (such as CHEK2, BRIP1, and RAD50)
3. If I test positive for certain genes linked to an increased risk for breast cancer, what should I do next?
Based on the risk level, there will be different levels of recommendations. Those with a high-risk gene will have options of increased surveillance as well as risk reduction options like medication and surgery. Those with moderate risk will more likely be given recommendations for increased surveillance if there aren’t other factors involved. For example, if you have a moderate-risk gene but also several familial links, the recommendation may include risk-reduction options.
4. Can you test for other cancers?
Yes. Many of the genes associated with increased risk of breast cancer include increased risks of other cancers, such as ovarian, pancreatic, prostate, melanoma or colon cancers. Similarly to breast cancer, those genes fall into certain risk categories and recommendations will be based on the risk level.
5. Who should get genetic counseling?
Genetic counseling can be appropriate for many people to make informed decisions about their cancer risk, as well as their family’s cancer risk. Meeting with a genetic counselor doesn’t mean you’ll automatically need genetic testing. We take a detailed medical and family history to help people decide whether genetic testing is right for them. Genetic testing may be most beneficial for people with one or more close family members diagnosed with cancer, anyone diagnosed with cancer under the age of 60, anyone diagnosed with a rare cancer or tumor (or more than 10 colon polyps), or with multiple cancers in their family. Genetic counselors can also discuss ways to lower your cancer risk, even if genetic testing isn’t an option for you.
Things to Know If You Choose to Get Genetic Counseling.
Those interested in genetic counseling do not need a referral from their physician (though preferred), but medical records from a recent medical visit are needed for review by our healthcare team prior to the clinic appointment.
You can also call 832.325.7206 to speak with the genetic counselor, and learn more about the process and how to schedule an appointment.