As a cancer survivor, it’s only natural that you’d be concerned about how your cancer diagnosis would affect your family members in regards to their cancer risk. And while encouraging your blood relatives to pursue genetic testing might seem like the logical thing to do, 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 

According to experts, only 5% to 10% of cancers are related to genetics. That’s a small percentage! And only certain types of cancers, such as breast cancer, ovarian cancer, endometrial cancer, prostate cancer, colorectal cancer, and pancreatic cancer are more likely to be hereditary. When you think about it, that’s actually very good news. While you have no control over your genetics, you most certainly do have control over the lifestyle factors (smoking, excess drinking, unhealthy eating habits, not exercising, excess sun exposure) that increase your cancer risks. For certain individuals, though, genetic testing can be incredibly beneficial.

When Is Genetic Testing for Cancer a Good Idea?

Before making a final decision about genetic testing, it’s a good idea for you and/or your loved ones to create a family cancer history map. Your primary focus should be on filling in 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:

• Being diagnosed with cancer when younger than 50 years of age
• A genetic mutation such as BRCA1 or BRCA2
• Ovarian cancer, regardless of age
• More than 20 colon polyps 
• Cancer in a pair of organs, such as in both breasts or both kidneys
• The same type of cancer that you have been diagnosed with
• 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 breast cancer, ovarian cancer, pancreatic cancer, and/or aggressive prostate cancer.

If you see any red flags among your family history, your doctor (or your relative’s doctor) will likely recommend meeting 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 will determine whether or not genetic testing is something you could benefit from. 

The Results of Genetic Testing Can Trigger Strong Emotions

It’s important to keep in mind that you don’t have to go forward with genetic testing even if you or your loved ones fit the criteria for it. While having answers can be a good thing, genetic testing can 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, when someone discovers they’re at increased risk of developing cancer, that may mean their close relatives have the same risk. This means that it may be wise to discuss that with their close relatives and find out if they want to know the results (since the results could affect them, too) before undergoing testing. 

Finding out that you are at an increased risk of developing cancer can be scary. However, having that bit of knowledge may allow 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 your loved ones, we encourage you to contact us to learn more. Genetic testing is available through many of the Minnesota Oncology cancer centers throughout the state. Find a location convenient to you.