Billions of cells make up the human body, and each cell contains two copies of DNA. This DNA is combined in different patterns to form genes, which play a role in dictating features like eye color, height, and probably intelligence. You receive two copies of each gene: one from each parent. Certain combinations of DNA, called genetic mutations, may also predispose you to cancer.
Hereditary Breast and Ovarian Cancer (HBOC) is a syndrome caused by mutations in certain genes that predispose both women and men to developing breast cancer, and significantly increases the risk of ovarian cancer in women. Most of the time breast cancer is sporadic, or influenced by a combination of bad luck and certain exposures. However, about 10% of women with new breast cancer diagnoses may possess a genetic mutation responsible for their cancer.
Although mutations in BRCA1 and BRCA2 are the most well known culprits responsible for HBOC, there are many mutations in other genes, some of them known as moderate penetrance genes, which may also increase the risk of breast cancer. These genes include PALB2, PTEN, CDH1, and ATM to name a few.
10 Common Misconceptions About Genetic Testing and BRCA Mutations
1. Genetic testing is expensive
Not anymore. As the indications for genetic testing continue to expand, testing becomes more widely available and therefore less expensive. Some cancer experts believe that all breast cancer patients should undergo genetic testing, and thankfully if insurance does not cover testing, the maximum out-of-pocket cost will be $250. The majority of patients pay less than $100 and assistance is available for those who cannot afford to pay these costs.
2. I have breast cancer but I don’t have any family members with cancer, so I don’t qualify for genetic testing.
Not necessarily. If you were diagnosed with any type of breast cancer <45 years old, or triple negative < 60, or you are of Ashkenazi Jewish heritage you qualify for genetic testing. If you were adopted, or a large portion of your family’s history is unavailable (immigration, war, etc), then you may still qualify for testing.
3. BRCA mutations are only passed down to female offspring.
False. If you or your partner have a BRCA mutation, there is a 50% chance of passing it down to your offspring for each pregnancy, male or female. BRCA mutations can also increase the risk of pancreatic and prostate cancer, along with melanoma or a rare type of uterine cancer.
4. If I am diagnosed with a HBOC-related mutation like BRCA, I must have a mastectomy.
Not necessarily. Although we know that removing ovaries in women with a BRCA mutation improves survival, we do not have the same evidence for mastectomy. Ovarian and breast cancer are different in that there is not very good screening for ovarian cancer, but excellent screening for breast cancer. Some patients diagnosed with a BRCA mutation (or a similar mutation) elect to undergo high-risk screening instead of mastectomy, and this is a personal choice. Factors that affect this decision include risks of surgery, desire to breastfeed , or other quality of life issues like body image or sexual function.
5. If I have a HBOC mutation, I cannot avoid passing it down to my children.
This is no longer the case. If you are found to have a BRCA mutation and you would like to have children, ask your doctor to be referred to a Reproductive Endocrinology and Infertility (REI) specialist. This is a specialized gynecologist that can speak to you about preimplantation genetic diagnosis (PGD). PGD is a process that involves creating embryos using your eggs in a lab, and then selecting the embryos without a BRCA mutation for implantation back into your body. It sounds like weird science, but it may be covered by your insurance and it offers you the opportunity to eliminate BRCA from your future family.
6. I tested my genes on an ancestry website so I don’t need more genetic testing.
Probably not true. Direct-to-consumer testing, where consumers can order genetic analyses are marketed as a method to map your ethnicity going back multiple generations, pinpointing a region where your ancestors may be from. Some of these tests may reveal a genetic variant related to a BRCA (or other cancer-related) mutation but these tests are not comprehensive, especially for people with no Ashkenazi Jewish ancestry. If your ancestry-related genetic test did not reveal a BRCA mutation, you may still meet criteria for more complete genetic mutation that tests for different BRCA mutations (there are many) or a mutation in another gene. If your ancestry-related testing DOES reveal that you might have a BRCA or similar mutation, speak to a licensed genetic counselor before considering prophylactic surgery of any kind.
7. I have a VUS so I need prophylactic surgery.
False. A VUS, or variant of unknown significance, should not change your medical or surgical management. VUS results by definition have not been proven to increase an individual’s risk for disease or to be the cause of the disease within a family. In fact, approximately 90% of VUS results will be reclassified as normal, harmless variants once geneticists learn more about them. Medical recommendations should be based on personal and/or family history of a specific disease, and NOT a VUS.
8. I have a BRCA mutation and had my ovaries removed early, but I cannot receive hormone replacement therapy.
Not necessarily. Prophylactic salpingo-oophorectomy not only reduces your risk of ovarian cancer, but also breast cancer. The amount of circulating hormones in postmenopausal women on hormone replacement therapy is generally lower than the circulating estrogen produced by premenopausal ovaries. Many BRCA and breast cancer experts agree BRCA mutation carriers who have their ovaries removed before age 50 are eligible for hormone replacement therapy (HRT). HRT has many beneficial effects including maintenance of bone health and sexual function after menopause, along with decreasing menopausal symptoms such as hot flashes, which can seriously affect a patient’s quality of life. Several studies have demonstrated that hormone replacement therapy after removal of the ovaries in BRCA carriers does not increase the risk of breast cancer. However, the decision to take HRT is complex and should be discussed with a doctor who specializes in cancer care.
9. I cannot take birth control pills if I have a BRCA mutation.
False. Oral contraceptives have been shown to decrease the risk of ovarian cancer in BRCA mutation carriers who are temporarily deferring removal of their ovaries.
10. I already have breast or ovarian cancer, why do I need to know if it was caused by a gene?
Having a BRCA mutation might affect how well certain breast cancer treatments work, such as medications called PARP inhibitors. If you have a BRCA mutation and have children, they may want to know if they have a 50% chance of carrying a BRCA gene, as they can probably take steps to decrease their own risk of cancer. If you have a BRCA mutation and have not yet had children, knowing this information ahead of time will provide you with the opportunity to learn more about the assisted reproductive technology PGD to eliminate the risk in your future offspring.
Remember – Knowledge is Power!
If you would like to learn more about whether you need genetic testing, or what your genetic testing results mean for you or your family’s future, you can make an appointment to visit with a specialist here.
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