The BRCA mutation: Screening, breast and ovarian cancer prevention

In an editorial in the New York Times entitled “My Medical Choice,” Anjelina Jolie has come out publicly as a carrier of the BRCA1 gene, which places her at high risk for both breast and ovarian cancer.  She has undergone a prophylactic nipple-sparing mastectomy with plans for future removal of her ovaries to prevent ovarian cancer:

I choose not to keep my story private because there are many women who do not know that they might be living under the shadow of cancer. It is my hope that they, too, will be able to get gene tested, and that if they have a high risk they, too, will know that they have strong options.  Life comes with many challenges. The ones that should not scare us are the ones we can take on and take control of.

Kudos to Jolie for choosing to tell her story in such a measured and informative manner. Having referred dozens of high risk women for BRCA testing, only to see them avoid it year after year, I for one  hope that Jolie’s story will encourage women at high risk to get screened.

But I also recognize that not every woman with a suggestive family history wants to know her BRCA status.

And that, too, is a choice.

What most of you need to know

For the overwhelming majority of the rest of the women I see, and for almost  all of you reading this, the most important thing you need to know is buried within Jolie’s editorial, and it is this: “Only a fraction of breast cancers result from an inherited gene mutation.”

About 2% of women have a family history that suggests the possibility of BRCA mutation,  and only about 1/10  of one percent of women carry a BRCA gene mutation.

Thus, Jolie’s story, while compelling, is medically irrelevant to almost all women. But for a very few, it may be lifesaving.

Should you consider BRCA testing?

Not unless you yourself have had pre-menopausal breast cancer or have had ovarian cancer, or  have a strong family history of breast/ovarian cancer.  From the NCI, here are the recommendations for screening based on family history.

For women who are not of Ashkenazi Jewish descent:

  • two first-degree relatives (mother, daughter, or sister) diagnosed with breast cancer, one of whom was diagnosed at age 50 or younger;
  • three or more first-degree or second-degree (grandmother or aunt) relatives diagnosed with breast cancer regardless of their age at diagnosis;
  • a combination of first- and second-degree relatives diagnosed with breast cancer and ovarian cancer (one cancer type per person);
  • a first-degree relative with cancer diagnosed in both breasts (bilateral breast cancer);
  • a combination of two or more first- or second-degree relatives diagnosed with ovarian cancer regardless of age at diagnosis;
  • a first- or second-degree relative diagnosed with both breast and ovarian cancer regardless of age at diagnosis; and
  • breast cancer diagnosed in a male relative.

For women of Ashkenazi Jewish descent:

  • any first-degree relative diagnosed with breast or ovarian cancer; and
  • two second-degree relatives on the same side of the family diagnosed with breast or ovarian cancer.

What about prophylactic mastectomy?

Mastectomy was not Angelina’s only choice.  Mastectomy is effective at reducing the risk for breast cancer, but breast cancer mortality is not impacted due the effects of aggressive screening and excellent treatments for breast cancer when it is diagnosed in BRCA carriers who choose not to have a mastectomy on a preventive basis.  Thus, Jolie could have opted for aggressive screening with breast MRI and/or use of medication (tamoxifen or raloxifene) to cut her risk of breast cancer in half. But with the option for nipple sparing surgery, mastectomy appears less a barbaric operation than in the past, with only a small increase in risk for leaving the nipple behind.

The use of mastectomy is increasing, not just among BRCA carriers, but among women with early breast cancer or pre-invasive disease (DCIS and LCIS) that places them at higher risk for invasive cancer in the future.  I worry that mastectomy may be getting overused, and hope that Angelina’s story will not result in more women having surgery than is necessary.

What about ovarian cancer protection?

As a gynecologist, I’m particularly concerned about ovarian cancer in BRCA carriers.

Angelina’s decision to remove her ovaries and Fallopian tubes offers her the best odds of avoiding ovarian cancer, the disease that took her mother’s life.  Unlike mastectomy, which prevents cancer but does not reduce mortality, oophorectomy does reduce mortality form ovarian cancer.  Because the truth is, we have nothing to offer to women to effectively screen and diagnose ovarian cancer at early stages  (although we offer it, ultrasound is not effective screening on a population basis), and treatments are just not as good as what we have for breast cancer.  So BRCA carriers are offered prophylactic BSO in their 40′s or once childbearing is completed.  The procedure itself can often be done as an outpatient laparoscopic surgery.

We are beginning to understand that ovarian cancer may actually originate in the Fallopian tubes. Research is underway to determine if removal of the Fallopian tubes alone might provide similar protection as removing of both the ovaries and tubes.  It’s too soon to say how that will play out, but we are hopeful.

What most women do not realize is that we do have prevention for ovarian cancer.  It’s called the birth control pill, and taking it can lower the risk for ovarian cancer by 80%.

Margaret Polaneczky is an obstetrician-gynecologist who blogs at The Blog That Ate Manhattan.

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