The New York Times reports on a new study that finds the widely used genetic screening test for breast and ovarian cancer "misses mutations that help cause the disease." The test, taken by tens of thousands of women a year, looks for mutations in genes called BRCA1 and BRCA2. For white women in the United States, 5 to 10 percent of breast cancer stems from the BRCA genes. According to the study's authors at the University of Washington, the test missed mutations in about 12 percent of breast cancer patients who had a family history of the disease. This is not necessarily new cause for worry. As the Times writes, "experts have long known that the test misses certain types of mutations it is not designed to detect. But the new study is believed to be the most extensive effort to quantify how often that occurs."
What is perhaps more frustrating is the fact that Myriad Genetics, the Salt Lake City company that runs the test, has a monopoly on patents, lowering its incentive to develop new technologies, and enabling it to charge patients a whopping $3,000. If you feel like getting even angrier, read Salon's feature on the business of "breast cancer."
So what should we do while we wait for Myriad develop more thorough screening? (The company promises to have a new test available by the end of the year.) Well, according to the Times, "experts cautioned that the chances of such false negative results were much smaller for women who were not from such high-risk familes, so that most women who tested had little cause for concern." Additionally, "even Ashkenazi Jews, who have a relatively high incidence of mutations, tend to have specific types that are not likely to be missed by the test." But for those of us who are at high risk? Well, the study's authors recommend taking precautions as if you have a mutation, "even if none was found." This means starting your mamograms 10 years before your family members were diagnosed, keeping up semiannual visits to the OB-GYN and staying abreast (couldn't help it) of scientific developments.