Hereditary Cancer Genetic Testing

Genetic testing continues to play an increasing role in cancer care. Your genes influence many traits including your height, eye color, as well as cancer risk. Approximately 5-10% of all cancers are caused by a hereditary cancer condition due to a gene mutation that a person has had since birth. Individuals with a hereditary cancer condition have a predisposition to certain types of cancer.

Not everyone who has a hereditary cancer condition will have cancer in their lifetime. However, we can use this knowledge to increase cancer screenings or initiate them earlier. Additionally, other family members may also have the same hereditary cancer condition and be at risk for cancer. Medications and treatments for cancer have been developed to work better for individuals with certain hereditary cancer conditions. For these reasons, hereditary cancer genetic testing can provide valuable information for you and your family.

When is genetic testing recommended?

Genetic testing is recommended when a person or family has certain features that are suspicious for a hereditary cancer condition. First, certain types of cancer have a higher chance of being caused by a gene mutation. For example, approximately 20% of all individuals with pancreatic cancer have a hereditary cancer condition. All individuals with certain types of cancer are recommended to undergo genetic counseling/testing. Another suspicious feature is developing cancer at an earlier than expected age. Most cancers occur as an individual ages so cancers in a younger person (such as breast or colon cancer prior to age 50) warrants consideration of genetic testing. Finally, individuals from families with a strong family history of cancer (meaning three or more related individuals with cancer) may qualify for genetic testing. These cancers may all be the same cancer or related cancers. For example, breast, ovarian and prostate cancer can be genetically linked. A person with a family history of three relatives on the same side with these cancers may be offered genetic testing.

At WakeMed Cancer Care, our team assesses our patients for these indications and refers appropriate patients to our genetic counseling team for a genetic counseling appointment. You can assist in this process by collecting and sharing your family history of cancer with your provider. Knowing your family history of cancer, including who in your family has had cancer, what type and age of diagnosis, allows for a better assessment of whether genetic testing is recommended.

What happens in a genetic counseling appointment?

A genetic counselor is a medical professional with advanced training in genetics and counseling who works with families to investigate whether a hereditary condition is present. Because of the complexity of the test results and the emotions involved, genetic counselors guide patients through the genetic testing process, providing explanation and support at each step.

Genetic counseling appointments typically last 30-60 minutes and can be completed in person at any of our convenient Cancer Care locations or through a virtual video visit. During the appointment, the genetic counselor will gather a detailed family cancer history. Once all information is collected, the genetic counselor will discuss whether genetic testing is recommended as well as the benefits, limitations, and insurance coverage and implications of testing. If a patient chooses to proceed, a blood or saliva sample is collected and sent to a lab for analysis. Results are typically available in 2-3 weeks. Once results are back, the genetic counselor calls the patient to review the results and discuss next steps.

What are the different types of genetic testing results?

There are three types of test results. A positive result means a genetic mutation was identified that may increase your risk of cancer. Individuals with a positive genetic testing result will meet with a genetic counselor who will review what types of cancers are associated with this condition and what is recommended to address this risk. For example, Lynch Syndrome is a hereditary cancer condition associated with increased risks of colon, stomach, uterine and ovarian cancer most significantly. Individuals with this condition are recommended to have earlier and more frequent colonoscopies compared to the general population. Women are recommended to be followed closely by a gynecologist and consider a total hysterectomy once childbearing is completed.

The second type of genetic testing result is negative. Even if genetic testing results are negative, the genetic counselor may have recommendations for cancer screening based on your family history. Approximately 20% of cancers fall into the "familial cluster" category, meaning that cancer occurs within the family at a higher percentage than expected by pure chance. The increased occurrence of cancer in these families is probably due to a combination of environmental/lifestyle factors and unidentified genetic factors. Depending on your specific family history of cancer, you or family members may be recommended to have increased cancer screening.

The third type of genetic testing result is a variant of uncertain significance. If there is not sufficient information to determine if a unique sequence is harmless or harmful, then the laboratory will classify the variant as a variant of uncertain significance (VUS). The American College of Medical Genetics (ACMG) does not recommend that VUS results be used in clinical decision-making. A VUS should be treated as a negative result until proven otherwise. When additional information is known about a particular VUS, you will receive an update and follow-up guidance.

What are the insurance implications of genetic testing?

The Genetic Information Nondiscrimination Act (GINA) is a federal law that protects individuals from health insurance and employment discrimination based on their genetic status. This law does not apply to life insurance, long term care insurance, disability insurance or individuals employed by the military.

Cancer genetics is a rapidly changing field, with new discoveries happening all the time. As new genes are discovered, you may be offered updated cancer genetic testing.

If you have additional questions about cancer genetic counseling or testing, please speak to your provider or call 919-350-CURE (2873) to schedule an appointment with our genetic counseling team.

Meet our Genetic Counselors