Should all women be screened for BRCA1 and BRCA2?

Who should be tested — and when? These are the big questions people ask when it comes to genetic screening, especially for commonly known mutations.

Here's the opinion of Charis Eng, MD, PhD, founding chairwoman of the Genomic Medicine Institute and founding director of its Center for Personalized Genetic Healthcare:

It’s safe to say more people know about BRCA1 and BRCA2 than the average mutations. High-profile cases such as Angelina Jolie’s have brought attention to them.

The actress recently announced her decision to undergo preventive surgery to remove her ovaries and fallopian tubes after genetic testing revealed she has the BRCA1 mutation. She made absolutely the right decision because decades of research has shown that prophylactic removal of the ovaries and fallopian tubes in women with BRCA1 mutations is the only way to dramatically reduce the genetic risk of ovarian cancer. Ovarian screening does not work.

According to the National Cancer Institute’s most recent estimates, based on decades of research, up to 40 percent of women who inherit a harmful BRCA1 mutation will develop ovarian cancer by age 70. That contrasts with the nearly 1.4 percent of women in the general population who will develop ovarian cancer sometime during their lives.

Because of these compelling statistics, well-respected researchers recently have publicly supported offering BRCA1 and BRCA2 screening and testing to all women after age 30.

It’s a bold statement. But even as someone who believes in the power of genetic counseling and testing, I’m not sure we — as a healthcare system in this country — are ready for it.  Indeed, Jolie made a decision with her caregivers to have BRCA1/2 testing because her mother, aunt and grandmother have related cancers.  This is the power of knowing your family health history.

Population-based testing

This new opinion is based on recent results of a study among the Ashkenazi Jewish population.

People in this group have a much higher risk of having BRCA1 orBRCA2 mutations than the non-Ashkenazi general population.  For example, the frequency of people carrying a genetic mutation among the Ashkenazi population is 1.8 percent to 3 percent, compared to a mean of less than 0.07 percent in the non-Ashkenazi general population.

And in the study, women with a BRCA1 mutation, for example, had a 60 percent risk of developing breast or ovarian cancer by age 60. The crux of this study is that 50 percent of the families identified as having mutations also did not have a family history of breast or ovarian cancer.

Why is that important? Because family history is a major red flag for genetic screening.

I understand the concern. The argument is that current screening guidelines result in missed cases. Doctors may not know enough to recommend genetic screening when it could save lives. Or patients may not know enough to ask. And too often, a personal case of cancer is the first time a patient comes in for screening.

So the idea is to offer BRCA1 and BRCA2 screening to all women after age 30 in the hopes that we find more of these mutations before they lead to cancer.

Are we ready?

One day in the future, the healthcare system may be ready for such screenings. We’re not there yet, in my opinion.

Nobody likes to talk about cost, but it’s an important factor. Whether our current system could bear the cost of such a huge change is up for debate. The screening itself may be feasible, but offering lifelong surveillance to women identified with mutations could present capacity issues. The cost of genetic counseling is a factor, too, but such counseling is critical. Without it, not enough doctors have the expertise to put genetic screening results and implications into clinical context for patients.

But it’s also a question of research. Will we identify enough additional mutations and prevent enough new cancer cases through general screenings to make such a program worthwhile? I hope the answer is yes, but researchers will need to design large-scale studies to test that theory. And those studies will need to cover patients from the general population, not only a group that is at very high risk for BRCA mutations.

However, I agree that we — all of us — can do better now for the women who face breast cancer risks.

The first step is better education, both for patients and for doctors. If more doctors know about the crucial work that genetic counselors do, they will make more referrals when needed. If more patients know how to craft an accurate and thorough family health history, those doctors will have even better information to work with.

And women who are concerned should be proactive, because the first step in assessing your risk is asking. This is true whether you are a member of a very high-risk group, such as Ashkenazi Jewish women, or if you simply wonder what your risk level is.

Ask your doctor for genetic counseling. Genetic counselors are trained to help you determine which screenings may benefit you and protect your future health — and that includes screenings for BRCA1 andBRCA2. They also are trained to help you deal with what comes after a positive screening. They can help prepare you for critical conversations with surgeons about options such as prophylactic mastectomy, for example, and they’ll walk you through what to expect in terms of increased monitoring for cancer risk.

In the future, BRCA testing may become like a mammogram or colonoscopy — a routine part of care once you reach a certain age. But in the meantime, there are certainly steps we can take to protect more women from cancer.

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