The chances for a BRCA mutation is even higher for people of Ashkenazi (Eastern European) Jewish descent with one or more relatives who fit this description.

Speak with a genetic counselor.

If one or more close blood relatives fit these criteria, ask a doctor for a genetic counseling referral. A genetic counselor can discuss the risks and benefits of genetic testing.

If genetic testing is appropriate, the best person to test is usually the person with cancer. "After we identify the mutation that caused their cancer, we can test first-degree relatives ??” mother, sisters, daughters ??” to see if they also carry it," Lu said.

Carefully weigh testing's pros and cons.

It's also important to consider family members' feelings. That's because the test results may forecast their cancer risks as well.

"No matter what you decide, remember that finding out you have a gene mutation doesn't mean you'll definitely get cancer," Lu said. "And, learning you don't have a gene mutation doesn't guarantee that you won't get cancer."

Source: The University of Texas MD Anderson Cancer Center