The Breast Cancer (BRCA) Gene: Who, What, When, Why

What you know could save your life

Breast Cancer Testing with BRCA Mutations.

Interview with Dr. Susan Domchek (SD) Executive Director, Basser Center for BRCA; Director, MacDonald Women’s Cancer Risk Evaluation Center of the University of Pennsylvania.

MS: What’s the problem If you have the BRCA gene

SD: BRCA1 and BRCA2 are two genes that everyone is born with, but if you’re born with one bad copy of either of those genes, you have a significantly increased risk of developing or ovarian cancer.

The lifetime risk of ovarian cancer goes from 1.7% up to 40%, the lifetime risk of breast cancer goes from 13% up to 70%. Having a gene mutation for this is very significant.

MS: Who should be tested for this? 

SD: The people at highest risk of having an inherited mutation in one of these genes are:

1. People who have developed breast cancer early, particularly those diagnosed under 40

2. Those who have triple negative breast cancer (the cancer cells do not contain receptors for estrogen, progesterone, or HER2)

3. Men who develop breast cancer

4. Any woman with ovarian cancer

5. People with a strong family history of breast and ovarian cancer, and importantly,

6. Individuals who are Jewish descent who have breast or ovarian cancer or pancreatic cancer, and there’s even some discussions about whether or not we should be testing every woman who is of Jewish descent.  

MS: Why does it matter if you have this gene mutation?

I know it increases your risk of cancer, but what can be done about that?

SD: If we know that you have a gene mutation, there are things that we can do to detect the cancer at an earlier stage. For instance, we can increase people’s breast cancer screening using breast MRI, and more importantly we can do things to prevent cancer.

The most effective strategy we have is the prophylactic removal of the ovaries, which decreases the risk of both breast and ovarian cancer, and leads to women living longer because they’ve removed their ovaries.    

MS: When you say ovaries, the surgeon also usually take the fallopian tubes out as well because some ovarian cancer begins in the fallopian tubes.

SD: That’s right. When we say “ovaries” we’re really talking about salpingo-oophorectomy or removal of both the fallopian tubes and the ovaries.         

MS: BRCA 1 is a little bit of high risk than BRCA 2 for ovarian cancer. This of course is a big decision and beyond what we can talk about in this interview, but one of the really interesting things you talked about is the fact that there are so many women who are worried about taking estrogen and getting breast cancer.   

SD: Right.  

MS: It’s interesting to think that taking out the ovaries can reduce the risk of breast cancer. Yet, here’s a young woman who’s in surgical menopause because her ovaries and tubes have been removed.

Can those women take estrogen?   

SD: We have good screening for breast cancer. Most women with breast cancer are diagnosed in early stage and most women survived their breast cancer. But ovarian cancer is very different; we don’t have good screening. The women who are diagnosed with ovarian cancer are often diagnosed at a late stage, and most women with late stage ovarian cancer don’t do well. Ovarian cancers are real problem, and we’re taking out these ovaries mainly so people don’t develop ovarian cancer because it’s a very terrible cancer.

When these women are worried about taking estrogen, I remind them that they’re making estrogen now, and what we’re doing is just giving some back to them so to mitigate their menopausal symptoms. After you prophylactically remove the ovaries, getting hormone therapy back, actually decreases breast cancer risk; hormone therapy doesn’t seem to really increase it. It’s important for women to know hormone therapy is an option for them and that they need to talk to their doctor about it.         

MS: It’s very important that a woman who has her ovaries removed doesn’t have to feel that she’s going to face early menopause and all of the potentially negative things that come with it, but has the opportunity to protect her ovarian and breast cancer risk by having the surgery, and not add to that risk by replacing estrogen. 

SD: Exactly right. It’s important because there are a lot of women who are hesitant to have this very important surgery done because of very understandable concerns about how they’re going to feel and we have this opportunity to give them estrogen back and to really help mitigate those negative symptoms.

Family history matters. It's important to talk with your doctor about your family history of cancer and see if genetic testing is right for you. 

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