Cancer Treatment Centers of America

Genetic testing identifies risk of developing certain cancers

blog genetic testing

For many of us, being healthy to prevent disease is a top priority. To do so, we eat foods that are good for us and exercise regularly. But the inner workings of our bodies are complex and changes can occur at the genetic level for a variety of reasons. These changes, called mutations, have a role in the development of all cancers.

Genetic testing has increasingly been used as a tool to identify those who may be at a greater risk of developing a cancer that's passed on through a family line. Of all cancers, 5-10 percent are linked to inherited genetic mutations. We talked to Dr. Michael Kayser, Clinical Geneticist at our hospital in Tulsa, to find out about genetic testing, who should get tested and when.

What are the most common genetic tests available?

The most common test is for BRCA 1 and BRCA 2 gene mutations, which are associated with breast, ovarian, prostate and pancreatic cancers. Women whose mother and/or sisters have been diagnosed with breast or ovarian cancer may want to pursue genetic testing. Breast cancer, in particular, is common, affecting one in eight women. We have many different screening modalities for breast cancer: self-exam, clinical exam, mammography, MRI and ultrasound. Genetic testing helps determine if your risk is low, average or high. Your doctor then can develop a more personalized screening plan for you.

Who should undergo genetic testing?

Insurance companies have certain criteria for reimbursement for genetic testing for BRCA mutations and for the five genes associated with Lynch syndrome, which is hereditary nonpolyposis colorectal cancer. Lynch syndrome is also linked to other cancers, including uterine, ovarian, breast, pancreatic, stomach, liver and brain cancers.

Typically, you must be diagnosed before age 50 and have multiple family members in multiple generations who have the cancer. Most of those family members also must have been diagnosed at a young age. The Affordable Care Act, commonly known as Obamacare, requires insurance plans that began on or after Aug. 1, 2012, to cover the cost of BRCA testing recommended by a clinician.

Should family members of cancer patients get tested?

I think it’s very personal decision. I’ve seen more than 4,000 patients in the past seven years. Some women want to do every test in the world, thinking it’s just a matter of time they will develop breast or ovarian cancer. The majority of these tests come back normal, meaning they don’t carry the mutated gene. Other women come in with a long family history of breast cancer and aren’t worried at all.

My main message to women is to be aware of what’s in their family history and pay attention to their test results. Ultimately, we want to prevent cancer. If it can’t be prevented, we want to diagnose it early so patients have better outcomes. Of the women who have breast cancer, less than 10 percent carry a BRCA gene mutation. Of those with colorectal cancer, 5-10 percent have the gene mutation for Lynch syndrome. It’s important to know that genetic mutations are rare though cancer is common.

What are the benefits of testing?

If you learn that you carry one of these gene mutations, you can act on it. Many women who learn they have a BRCA mutation today opt to get surgery to remove their breasts and ovaries. By removing their ovaries, they reduce their risk of cancer by 95 percent. Similarly, having a double mastectomy decreases their risk of breast cancer by 90 percent.

If you don’t carry a mutation, that knowledge may reduce your anxiety. But you should still be aware that cancer affects many people and you should strive to make choices to help prevent it. Don’t smoke, eat a healthy diet, exercise and get regular screening tests.

Read about a U.S. Preventive Services Task Force recommendation that only high-risk women get BRCA testing.

Learn about genetic testing at our hospitals.