Breast cancer gene?

Originally Published: December 1, 1994 - Last Updated / Reviewed On: November 28, 2014
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Dear Alice...

I am an undergrad here. My maternal grandmother had (and survived) breast cancer before the age of forty. In her thirties, my mother had breast cancer (it was advanced, but she recovered), only to (a few years later) be diagnosed with ovarian cancer, which was unfortunately terminal. I know that given these two facts, it is likely that I may be at a higher risk, and my doctors at home watch me carefully. Given the discovery of BRCA-1 (the breast/ovarian cancer gene), I am wondering what to do — should I be tested? Will it matter? I have made an appointment with a women's health care provider to get some advice, but I still wanted to ask you.

Also, I was wondering if you know if it is possible (or advantageous) to see if I could get my mother's medical records — is this legal? I am not sure what, if anything, I should be doing now (besides exercising, eating right, etc., the obvious)...

Thank you...
Nature or nurture?

Dear Nature or nurture?,

Neither having a family history of cancer nor discovering you are positive for mutated BRCA1 or BRCA2 genes means that cancer is inevitable. Knowing these things, however, helps health care providers understand the level of risk you might have for breast and certain other cancers. The question of whether or not you should undergo genetic testing (for BRCA1 and BRCA2 mutations) is a decision best made by working with your health care provider, a step you’ve already planned to take. Same goes for accessing your mother’s medical records – it’s possible they could be helpful, but they probably aren’t needed at this stage of the game. Let’s delve a little deeper into a conversation about the BRCA1 and BRCA2 genes.

Both men and women have BRCA1 and BRCA2 genes (short for BReast CAncer Susceptibility Gene 1 and 2), but it’s the mutation of these genes that is associated with an increased risk of breast and ovarian cancers. These genes create tumor suppressor proteins which help repair damaged DNA. The chance of inheriting a mutation is 50 percent if a patient’s mother or father has a BRCA1 or BRCA2 mutation. If someone has a confirmed mutation, it typically means that one of their parents also has it (except for in very rare cases). Men and women with these gene mutations are at a higher risk of developing breast cancer compared to those who have normal BRCA genes, and may be at increased risk of other cancers.

According to estimates of lifetime risk, a woman who has inherited a harmful mutation in BRCA1 or BRCA2 is about 4 to 5 times more likely to develop breast cancer than a woman who does not have such a mutation. Among women in the United States, it is estimated that these inherited mutations account for 3 to 10 percent of breast cancers (it’s still rare for men, even with a BRCA1 OR BRCA2 mutation). The gene mutations are also linked to various other types of cancer. For women, BRCA1 mutations are linked to fallopian tube and peritoneal cancers. BRCA2 mutations have a strong association with the risk of testicular and prostate cancer for men. Both mutations are linked to pancreatic cancer in men and women. Individuals who have a personal or family history of breast cancer may want to consider genetic testing to learn more about her/his personal cancer risks (particularly if two or more close relatives had it, it was present in multiple generations of her/his family, or if it developed in relative(s) at an early age). Using The Penn II Risk Model may help you determine your personal and familial risk of having the BRCA1 or BRCA2 gene and whether you’d be a good candidate for genetic testing.

You also may want to think about how the results of genetic testing will impact your life. Not all BRCA gene mutations carry the same amount of risk, so a genetic counselor will be particularly helpful in assessing your medical health, lifestyle, and family history. S/he can also work with you to create a strategy for managing your personal cancer risks. Other considerations include potential discrimination and cost. Although genetic discrimination by insurance agencies or employers is prohibited (following the passage of the Genetic Information Nondiscrimination Act), life insurance, disability insurance, and long-term care insurance are not covered. A positive BRCA1 or BRCA2 test result in a patient’s medical records could affect her/his coverage/insurance costs. Additionally, the cost of the BRCA test itself can vary depending on your insurance coverage, so you may want to find out about your insurance company’s policies regarding genetic tests. Per the Affordable Care Act, the cost of genetic testing and counseling may be covered for some people if it's recommended by her/his health care provider. If you decide that genetic testing is an option you'd like to take, only a blood sample is required, but results may take several weeks or even months.

While the results of the test may be informative, the test also has limitations. Most notably, a negative result is not a guarantee that cancer will not eventually develop, and finding an altered BRCA1 or BRCA2 gene will not indicate if or when cancer could develop. In the case of a positive result, knowledge of a BRCA mutation would signify the need for more careful monitoring by your health care provider. Risk management options include:

  • Surveillance, including frequent clinical breast exams and mammograms.
  • Chemoprevention is the use of drugs such as tamoxifen and raloxifene to reduce breast cancer risk. These drugs have been effective in reducing breast cancer among high risk women, although it is unclear whether this is true for women with BRCA mutations.
  • Lifestyle changes, such as changes in diet and exercise.
  • Some women choose to have risk-reducing surgery to reduce a patient’s chance of developing breast cancer by up to 90 percent. A prophylactic mastectomy is only recommended for patients perceived as having a high breast cancer risk. Removal of a woman's ovaries and fallopian tubes to reduce the risk of ovarian cancer is also a prophylactic option. However, these surgeries will not guarantee a woman will not get cancer.

If you discover you are at high risk for developing breast cancer, having an honest conversation with your genetic counselor or health care provider about appropriate preventive actions may give you some peace of mind. If at any time you are referred to a genetic counselor or a cancer specialist, they may want to know more about your family history. Depending on the medical facility and the laws governing them, you may or may not have access to these files. Therefore, it might be helpful to have her/him look at those records, if they are still available.

You can also check out more information about Cancer Genetics at the National Cancer Institute's (NCI) website. It's admirable that you are exploring options with consideration of your present and future personal health. Best of luck reaching a conclusion that supports your health and happiness.

Alice