"I carry a 'faulty' gene, BRCA1, which sharply increases my risk of developing breast cancer and ovarian cancer," Angelia Jolie revealed in the New York Times today, explaining her decision to undergo a double mastectomy.
BRCA1 is one of two genes that doctors can test for certain mutations that would indicate a high risk of breast cancer (the other gene is BRCA2). The risk was first discovered in 1994 by a team of researchers at the University of Iowa. Since then, a company called Myriad Genetics came up with a test called BRACAnalysis that could determine whether a woman has the risky mutation.
That means, as Jolie writes, that it is now "possible to find out through a blood test whether you are highly susceptible to breast and ovarian cancer, and then take action."
The big question in medical research, though, is whether most women should. Figuring out which women should have the expensive screening for a relatively rare genetic mutation is a vexing task. Researchers have no bright line between the portion of the population that is and is not at risk.
Researchers estimate that 0.11 to 0.12 percent of women in the general population carry either of the BRCA mutations. The prevalence is higher among certain ethnic groups, such as Ashkenazi Jews, where it is estimated that 2 percent of women carry the mutation.
The BRCAnalysis screening costs as much as $3,000 but is about to get significantly less expensive: The Affordable Care Act included the genetic test among the preventive services that insurers are required to cover without any cost sharing.
"Genetic counseling and BRCA testing, if appropriate, must be made available as a preventive service without cost-sharing," the Department of Labor wrote in a March 9 document that clarified some of the health law's preventive benefits.
That "if appropriate" bit above is important. The United States Preventive Services Task Force and other groups do not think that the BRCA screening is appropriate for women without a history of breast cancer.
The USPSTF recommended against widespread BRCA screening in 2005 and reiterated that stance in draft recommendations made last month. The task force gave widespread screenings a "D" grade, meaning that it would expect "no net benefit."
"For women whose family history is not associated with an increased risk for potentially harmful mutations in the BRCA1 or BRCA2 genes," the task force wrote, "there is moderate certainty that the net benefit of testing for potentially harmful mutations in the BRCA1 or BRCA2 genes and early intervention ranges from minimal to potentially harmful."
The potential harms are, as the task force describes it, small, and mostly have to do with the psychological stress of undergoing a potentially life-altering test. Still, when the task force doesn't see benefits, it does not recommend the widespread use of a test that would not be expected to provide any benefits.
BRCA testing is recommended in a more limited context, for women with "increased family risk" history, such as multiple cases of breast cancer in the family. The task force recommends that "primary care providers should ask about specific types of cancer, which family members were affected, and the age and sex of affected family members."
Perhaps the most challenging part though is there's no clear line, after that initial evaluation is done, between what type of family history does or doesn't indicate a need for BRCA testing. "There is no empirical evidence concerning the level of risk for a BRCA mutation that merits referral for genetic counseling," the task force writes. Under the health law, it's largely left to doctors to decide what counts as an appropriate test and what doesn't.