Positives and negatives of genetic test results

04.23.2019

Tempted to try an at-home genetic test kit that can tell you about your cancer risks? Online options or drug store kits sound simple to use. Spit in a tube, mail it to a lab, get the results.

But what do the results really mean? And what can you do with the information, whether it’s positive or negative?

Most people need professional guidance not offered through at-home testing to understand risks and potential implications for family members.

The best way to get a full picture of your cancer risk is to start a conversation with your doctor. With help from medical experts, you can better understand how family history, environment and lifestyle choices effect chances of developing cancer or other health conditions.

“A healthcare provider who prescribes genetic testing can accurately interpret results and discuss appropriate disease prevention or treatment,” said Dr. Fiona Denham, Surgical Oncologist at Goshen Retreat Women's Health Center. 

Counseling before and after genetic tests

Unlike online-order testing kits, Goshen Health offers a comprehensive approach to assessing cancer risk for men and women. It includes genetic testing through a reputable lab and pre- and post-test counseling by providers like Dr. Denham who are trained in managing inherited cancers.

“We first want to make sure genetic testing is right for you,” explained Dr. Denham. During hour-long consultations, genetic experts at Goshen Health take an in-depth look at a patient’s family history with cancer and other health risks. They also look at clinical guidelines to decide if it is appropriate to do genetic testing.

Providers at Goshen Health who recommend genetic testing use a nationally known and validated lab to look at multiple genes (panel testing) that can indicate risk for hereditary cancers including breast, ovarian, colorectal, prostate, pancreatic and others.

When test results come back from the lab, trained professionals talk with patients about what positive or negative results mean. Counseling also helps patients make informed medical decisions about interventions and treatments.

Limitations of direct-to-consumer tests

In January, 23andMe received FDA approval to provide test results for a hereditary colorectal cancer syndrome called MUTYH-associated polyposis. Limited testing for breast cancer also is available.

However, genetic tests sold directly to consumers by testing labs do not tell a complete story about risks for developing cancer. They also do not provide information that you can use to make medical decisions.

Is genetic testing right for you?

Most people don’t have a strong family history or inherited connection with cancer. Inherited mutations – like the ones consumer testing companies test for – play a role in only 5 to 10 percent of all cancers.

If you think you are at risk for developing cancer, talk with your doctor. Trained healthcare providers like Dr. Denham can help you understand how factors passed from one generation to the next may increase your risk for several diseases.

Know your family history

“Your family history is the most important piece in understanding your actual risk for cancer,” said Betsy Garber, Family Nurse Practitioner at the Retreat.

That’s why trained genetic professionals look at three generations on both sides of your family. Age, gender, cause of death and other factors can lead to important clues about what you may have inherited in your DNA.

Screenings save lives

Negative results are no substitute for regular preventive screenings, like colonoscopies or mammograms. Preventive screenings can detect cancer early when you have more treatment options, like less-invasive surgeries or medications with fewer side effects.

For more information about genetic testing, contact Goshen Health, (574) 364-4600.