Q&A: Genetic counseling after a cancer diagnosis

I was diagnosed with ovarian cancer two months ago. My oncologist recommended that I undergo genetic testing as part of the treatment plan. Why is it recommended since I already have cancer? What is the benefit of testing? And what information will it provide?

ANSWER: Genetic counseling can be an important part of a cancer journey. A genetic test looks for specific harmful genetic changes, called pathogenic mutations or variants, that can cause a person to develop a genetic disease. Genetic changes are like misspellings in the body’s instruction manual.

Most genetic tests look for changes in a group of genes called a panel. However, tests can look for changes in a single gene when there is a known genetic mutation in your family. The genes most commonly associated with cancer risk are BRCA1 and BRCA2. These genes are associated with breast and ovarian cancer. It is known that changes in other genes can also increase the risk of these cancers.

Along the cancer journey, genetic testing can help your healthcare team make recommendations for treatments and surgeries. For example, some cancers associated with genetic mutations respond better to certain types of chemotherapy treatments than to others. Likewise, genetic testing can help patients make surgical decisions. For example, a patient with breast cancer can use the information to determine between a lumpectomy or a mastectomy. Genetic testing can also affect cancer risk management over time.

Genetic test results can help your family members. Potentially, your children, siblings, nieces and nephews could have inherited the same genetic mutation. For example, if you had a change in the BRCA gene and tests showed it, your family members have a higher risk of breast and ovarian cancer. Knowing this information can be invaluable in helping them establish early screening schedules and make healthy decisions throughout their lives.

It is important to know that most cancers are considered sporadic, which means that the cancer occurs randomly or has environmental influences, such as smoking and lung cancer. About 25% of cancers are considered familial. This is when several members of a family are affected by cancer. These family members have common genetic factors in combination with common environmental factors that lead to the development of these cancers.

About 10% of cancers are considered hereditary or have a single specific genetic component that can be tested for and increase the risk of developing cancer. Genetic counseling and genetic testing can help determine which category your cancer is in.

Many other health problems have a genetic link. Genetic testing can help you and your healthcare team understand if you have an increased risk of developing other conditions that run in your family. If you are at risk, you may be able to take preventive measures to reduce your risk or undergo genetic testing to clarify your risk.

Although you cannot change your genes, you can control certain aspects of your environment, such as diet and level of physical activity, as well as alcohol and tobacco consumption. That’s why it’s still so important to lead a healthy lifestyle, regardless of your personal and family genetic background.

©2022 Mayo Clinic News Network.

Distributed by Tribune Content Agency, LLC.