What is Genetic Testing?
Genetic tests are done to look for specific changes or mutations in a person’s chromosomes, genes or proteins. It is used to identify genetic conditions or a person’s risk of either developing a genetic disorder or passing on an inherited disease to a future generation. For people with a family history of cancer, it’s an important tool that can help identify the potential for problems, make decisions to monitor for early detection, or to decrease or prevent the chance of future disease. A genetic counselor can help a patient with understanding the potential benefits of genetic testing.
Cancer that appears to run in families isn’t always caused by an inherited mutation, but rather shared environments or lifestyles. If a patient does test positive for an inherited genetic mutation, it is not a certainty that they will develop cancer.
The tests are done on blood and other tissue samples. At the time the test is done, a patient doesn’t necessarily have cancer but may have a family history so they are choosing genetic testing as a proactive approach as a means of awareness.
Genetic tests results can help an oncologist
Determine if further testing is necessary.
Customize a cancer screening plan that may differ from the currently recommended ages for these tests.
Suggest strategies that can help a patient lower their risk of developing cancer.
Cancer awareness is key in finding the disease early when the chances for a successful cure are the highest.
Oncologists order a genomic analysis test on tissue samples from a cancerous tumor to look for genetic mutations. Cancer has different types of biomarkers which can be identified in the genes and proteins that make up a tumor. Just as every cancer is different, each person’s biomarkers are different.
The test looks at the entire genetics (DNA) which gives important information about how aggressive the cancer is, how well the cancer is likely to respond to chemotherapy treatment, and gives a ranking that indicates the likelihood of a later recurrence. This helps the oncologist determine the correct type of treatment for cancer.
It also provides invaluable information about whether the cancer is likely to spread to other parts of the body or if cancer has an actionable mutation, which is an abnormality in the genetics of the tumor cells for which there is either an FDA approved targeted agent or one that is currently in trial or part of a future trial.
A genomic test can be used for certain types and stages of breast cancer, early-stage prostate cancer, and some stages of colon cancer. The information learned from these tests helps oncologists determine the best course of treatment. These tests can also indicate how aggressive the cancer is, who may benefit from immediate cancer treatment, or who can choose active surveillance.