What you need to know about the breast cancer gene and Angelina's mastectomy

After finding out she had "the breast cancer gene," Angelina Jolie decided to have a double mastectomy to significantly reduce her risk of cancer. Should you get tested for the gene, too?

She’s an actress, director, humanitarian and Academy Award winner. And now Angelina Jolie is breast cancer-awareness advocate as well, sharing her personal experience with the disease.

In an op-ed in The New York Times, Jolie revealed that after learning she carries the so-called breast cancer gene (BRCA1) she opted to undergo a double mastectomy. Her decision was based on her own mother’s bout with cancer, which took her life at age 57, and Jolie's desire to remain healthy for her six children. But in revealing her choice (she had simultaneous reconstruction surgery using breast implants, so she could have kept it a secret) she aims to help other women have the same chance to stop cancer before it starts.

“I am writing about it now because I hope that other women can benefit from my experience,” Jolie writes. “Cancer is still a word that strikes fear into people’s hearts, producing a deep sense of powerlessness. But today it is possible to find out through a blood test whether you are highly susceptible to breast and ovarian cancer, and then take action.”

Women in general have a 12 percent risk of developing breast cancer, according to America's National Cancer Institute (NCA). For women with the BRCA1 gene mutation, that risk increases to 60 percent. Jolie's doctors estimated she had an 87 percent risk of developing breast cancer. BRCA1 also increases a woman’s risk of ovarian, cervical, uterine, pancreatic and colon cancers. A similar mutation in the BRCA2 gene increases a woman’s chance of breast and ovarian cancer as well as pancreatic, stomach, gallbladder and bile duct cancer and melanoma.

Around 5 per cent of the 14,000 breast cancers diagnosed in Australia each year, or about 700 cases, are linked to inherited gene mutations,

What is BRCA testing?
Genetic testing for the BRCA gene is only recommended for people with a strong family history of breast cancer. The blood test looks for mutations, or errors, on the BRCA1 or BRCA2 genes to determine whether a woman is at higher-than-average risk for breast and ovarian cancer.

BRCA-related cancers usually involve both breasts and are more likely to occur at a younger age. Currently there is no recommendation for who should be tested for BRCA gene mutation, but the NCA says you should consider genetic counseling to learn more about your potential cancer risk if:

–You have two first-degree relatives (mother or sister) who've had breast cancer, one of whom was under age 50 at diagnosis.

–You have three or more first-degree or second-degree (grandmother or aunt) relatives diagnosed with breast cancer.

–You have a combination of first- and second-degree relatives diagnosed with breast cancer.

–You have a first-degree relative diagnosed with cancer in both breasts.

–You have two or more first- or second-degree relatives diagnosed with ovarian cancer, or a combination of first- and second-degree relatives diagnosed with ovarian cancer.

–You have a male relative with breast cancer.

–You are of Ashkenazi Jewish descent, particularly if a first-degree relative has been diagnosed with breast or ovarian cancer. The risk also increases if two second-degree relatives on the same side of the family have been diagnosed with those cancers.

What the results tell you
Your BRCA status is not necessarily your fate. If the results come back positive for a BRCA gene mutation, it doesn't mean you'll definitely get cancer, it means that you have a higher risk of developing the disease. "People can have this gene change and never have cancer," says Kathy Helzlsouer, director of the Prevention and Research Center at Mercy Medical Centre. "About 10 percent of breast cancers are inherited, and of those, about half are due to a gene change in BRCA1 or BRCA2. The other half of suspected inherited types of cancer is not currently explained." People without the BRCA gene can still develop breast cancer.

Before you opt for the test, though, make sure you're ready for the results. "You need to really think, 'Am I ready to learn this information?'" says genetic counselor Joy Larsen Haidle. "'How am I going to use that information and am I going to do something different if I have it?' If the answer to any of those questions is 'no,' then while the test is available, it might not give you the same benefit that it would for somebody else who answered 'yes' to some of those same questions."

Not everyone chooses prophylactic mastectomy like Jolie did. Other options for BRCA carriers include regular cancer screening and surveillance to catch cancer at its earliest and most treatable stage, and a regiment of chemoprevention with the use of drugs such as Tamoxifen and Raloxifene.

For women who've never had cancer, testing positive for a BRCA mutation can significantly affect their reproductive years. Routine breast and ovarian screenings are recommended, but because ovarian cancer screening is not proven effective, and the disease often shows no symptoms until it is far advanced. Women are advised to make decisions about having children earlier rather than later.

"The current recommendation is once they're done with childbearing and they're close to that 40-year-old mark, they should consider getting their ovaries and fallopian tubes removed," says Helzlsouer. "Those are hard, hard decisions."