Breast Cancer

Are You A Candidate For Breast Cancer Testing?

Because breast cancer is one of the most common cancers, the test women are most often asking about is the one for BRCA mutations. A Salt Lake City-based company called Myriad Genetics has patented the BRCA genes and performs genetic testing. The lab testing is complex, but all that is needed from you is a blood sample.

It is important to remember that even when a family has a mutation, not everyone will inherit it. You have two copies of every gene. If one of your father's two copies of, say, BRCA1, has a mutation, your chance of inheriting that mutation is 50 percent. Thus, in a group of siblings, some will inherit a mutation, others won't. If your sister has breast cancer and you don't, she's the better candidate for testing, because if you test negative for a mutation, it may mean there's no mutation in the family, or may simply mean you didn't happen to inherit it. The result gives no guidance for the rest of your family.

An initial comprehensive analysis of BRCA1 and BRCA2 costs $2,580; if a mutation is identified in the first person tested, subsequent tests for other family members are $295 each. The reason the first test is so expensive is that the genes must be fully sequenced to identify the mutation. Once a mutation is found, the technicians know where exactly to look in the other relatives' DNA samples. A variation of the test that looks only at three specific mutations found in the Ashkenazi Jewish population (Eastern European background) is $350.

If no one in your family has been diagnosed with breast or ovarian cancer, then your risk of carrying a BRCA1/2 mutation is very small and testing would not be recommended. Keep in mind, however, that absence of these mutations doesn't mean you won't develop cancer. At least 90 percent of breast and ovarian cancer cases are "sporadic," meaning they don't stem from inherited mutations, but rather are caused by a mutation, or combination of mutations that arise over time. Therefore, regardless of your genetic status, be sure to take precautions such as having a once-yearly breast examination by your health care professional (called a clinical breast examination) and a mammogram, if appropriate (schedule based on age).