A family history of cancer does not mean you’ll get cancer too.
“No genetic test can tell if you will develop cancer for sure. But it can help you and your family navigate your concerns about genetic conditions and associated cancer risks.”
Cancer genetic testing can help you and your doctor decide if there are steps you can take to lower your cancer risk or to guide your treatment options if you are diagnosed with certain types of cancer. A critical part of genetic risk assessment is the responsible and appropriate disclosure of test results. More so because genetic testing can give several possible results: positive, negative, true negative, uninformative negative, variant of uncertain significance, or benign variant. The anxiety and stress associated with genetic testing can be decreased to a large extent if you are guided by trained professionals who can answer your questions and explain the results appropriately.
What do the test results mean?
A positive result does not mean you will get cancer in your lifetime; it gives a risk assessment of the possibility of developing cancer higher than the normal population.
A Positive Result means that the testing found a genetic mutation that is associated with an inherited cancer susceptibility syndrome. For a person who has cancer, a positive result confirms that the cancer was likely due to an inherited genetic variant and can help guide treatment choices. A positive result can also indicate an increased risk of developing certain cancers in the future and guide future planning to lower that risk. It can also provide important information that can help other family members make decisions about their own healthcare, such as whether to have genetic testing to see if they have also inherited the variant.
A Negative Result means that the testing did not find the specific variant that the test was designed to detect. This result is most useful when a specific disease-causing gene mutation is known to be present in a family. In this situation, a negative result can show that the tested family member has not inherited the mutation that is present in their family. Such a test result is called a true negative. A true negative result does not mean that there is no cancer risk, but rather that the risk is probably the same as the cancer risk in the general population.
An Uninformative Negative shows up when a person has a strong family history of cancer but the family has not been found to have a known mutation associated with a hereditary cancer syndrome. It means the test result does not provide useful or immediately actionable information. Such a negative test does not preclude further testing, and your cancer care team will decide the frequency and type of cancer surveillance you need based on other risk factors you may have.
Variant of Uncertain Significance (VUS) means that the genetic testing shows a mutation that has not been previously associated with cancer. This result may be interpreted as uncertain, which is to say that the information does not help to clarify their risk and is typically not considered in making health care decisions. It is important for the person who is tested to keep in touch with the provider who performed the genetic testing to ensure that they receive updates if any new information on the variant is learned.
Benign Variant is when the test reveals a genetic change that is common in the general population among people without cancer. Everyone has commonly occurring benign mutations that are not associated with any increased risk of disease.
Genetic counseling by trained, certified professionals provides the right framework for informed decision-making, coping with the psychosocial and personal ramifications of your genetic risk, and protecting patient confidentiality and privacy. It is one of the many tools in the arsenal of your cancer care team to provide you with the appropriate care you need. The next steps after getting your results can include major decisions such as surgery, so it is important for you and your family to understand both short- and long-term risks and be comfortable with the choices you make. Speak to your doctor or cancer care team regarding genetic counseling for cancer.