What is genomic testing?

Genomic tests do not focus on single genes. Instead, genomic tests look at several genes or proteins in one test. The variations in our DNA code or in the proteins produced by our genes may be found in a blood sample (if they were passed on to us at birth) or in disease tissue, such as a tumor.

The variations detected in cancer genomic tests can help us predict:

  • Who is more likely to get certain types of cancer
  • Which tumors are more likely to spread (or metastasize)
  • Which tumors are more likely to respond to a specific treatment, such as chemotherapy

Physicians are increasingly using genomic tests for patients with specific cancers. One genomic test, called Oncotype DX™, is currently available for women with early-stage breast cancer. This test looks for specific DNA variations in a woman’s breast tumor that predict whether the tumor is likely to spread and whether the woman would benefit from chemotherapy. For people who have tumors that are unlikely to spread and that won’t respond to chemotherapy, this genomic test helps them avoid the side effects and the risks of chemotherapy. In this way the test helps doctors make targeted treatment decisions for each person.

Some genomic tests identify gene variations that can select out those individuals with the highest risk of certain cancers. Because these gene variations are present at birth (so they are present in blood cells), people can be tested before getting cancer, to predict who is more likely to get a certain cancer. Currently, these types of genomic tests are not generally available.

Scientists are searching the entire DNA code of people with and without disease (including cancer, diabetes, heart disease, and more) to find DNA variations among these individuals. By identifying through research the DNA variations that can predict who is more likely to get a certain disease, genomic tests can be developed. Such tests will help us understand each person’s specific disease risks. With this type of information, individuals can focus on reducing their specific risks and begin screening early for diseases they are most likely to get. Knowing their specific disease risks can encourage people to take better care of their health. They can take targeted steps to reduce their risks (such as changes in their diet), and they can have earlier and more frequent screening tests (such as colonoscopies) to find disease early, when it can be treated most effectively.

Genomic tests are part of a revolution in medicine that is often called personalized medicine. In the new era that this term describes, we will focus on disease prevention and targeted treatments that are specific to each person. With the use of genomic tests, our approach to healthcare will be more “personalized” than ever before.

To learn more about genomic testing, and specifically the Oncotype DX genomic test for early-stage breast cancer, go to http://www.mytreatmentdecision.com/310-oncotype-dx.aspx.