Who Should Get Genetic Testing?

Portrait of happy multi-generation family standing outdoors

As a cancer survivor, it’s likely some new or different concerns are on your mind these days, including how your cancer diagnosis might affect your family members in regards to their own cancer risk. While it might seem logical to encourage your blood relatives to undergo genetic testing, it’s important to understand that genetic testing is only helpful in predicting cancer in a small percentage of individuals.

When It Comes to Cancer Risk, Lifestyle Trumps Genetics 

Most cancer diagnoses aren’t related to genetics but genetic testing can be very beneficial when deciding on a treatment option for cancer patients. Only 5% to 10% of cancers are related to genetics, according to experts. Additionally, only certain types of cancers like prostate cancer, colorectal cancer, pancreatic cancer, breast cancer, ovarian cancer, and endometrial cancer are more likely to be hereditary. Considering all the types of cancers there are, that’s actually very good news! While you have no control over your genetics, you most certainly do have control over the lifestyle factors (unhealthy eating habits, lack of exercise, smoking, overindulging in alcohol, excess sun exposure) that increase your cancer risks. For certain individuals, though, genetic testing can be very helpful.

When Is Genetic Testing for Cancer a Good Idea?

Undergoing genetic testing is not a decision that should be taken lightly, but rather one that requires careful consideration. Before making a final decision about genetic testing, it’s wise to create a family cancer history map that lays out the cancer histories of as many first-degree (parents, siblings, and children) and second-degree (grandparents, aunts, uncles, nieces, and nephews) relatives as possible. Genetic testing may be beneficial if one or more first- or second-degree relatives has been diagnosed with:

  • A genetic mutation such as BRCA1 or BRCA2
  • The same type of cancer that you have been diagnosed with
  • A cancer diagnosis when under the age of 50
  • More than 20 colon polyps 
  • Ovarian cancer, regardless of age
  • Cancer in a pair of organs, such as in both breasts or both kidneys
  • Rare cancers including sarcoma or male breast cancer
  • Two or more different types of cancer that have occurred independently in the same person

There are other genetic risk factors that should also be taken into consideration. These include certain ethnic predispositions, specifically Ashkenazi Jewish ancestry and/or having three or more relatives who have developed ovarian cancer, breast cancer, pancreatic cancer, and/or aggressive prostate cancer.

If any red flags are present among your family history, it’s likely that your doctor will encourage you to meet with a genetic counselor for genetic counseling. A genetic counselor is a trained professional who will be able to further pinpoint the odds of having a genetic mutation that raises the risk of certain types of cancers. The findings of the genetic counselor are what will determine whether or not you are a good candidate for genetic testing.  

The Results of Genetic Testing Can Trigger Strong Emotions

When it comes to genetic testing, only you can make the final decision as to whether it’s right for you. Even if you or your loved ones fit the criteria for genetic testing, you don’t have to go forward with it. After all, answers can be a good thing, but they can also be potentially life-changing. Because of this, it’s a good idea to consider and prepare for the “what-ifs” before you pursue it. Additionally, should you discover that you’re at increased risk of developing cancer, that may mean your close relatives have the same risk. Therefore, before undergoing testing, it may be a good idea to have a talk with your close relatives to see if they want to know the results (since the results could affect them, too). 

At Rocky Mountain Cancer Centers, we understand that finding out that you are at an increased risk of developing cancer can be scary. However, having that bit of knowledge may empower you to be proactive in ways that will reduce your risk (such as preventive mastectomies to reduce the risk of breast cancer). Furthermore, being at an increased risk for cancer doesn’t mean you will definitely develop it. If you would like to learn more about whether or not genetic testing is right for you and your loved ones, we encourage you to visit our Genetic Testing FAQs page.