Circulating Tumor DNA (ctDNA) Testing
What is ctDNA and ctDNA testing?
Circulating Tumor DNA (ctDNA) means that fragments (parts) of your tumor are in your blood. ctDNA testing is a blood test that can help find cancer. Testing can also be done after you have had cancer treatment or surgery to check if the cancer has come back (recurrence) or if you still have cancer (residual disease). If your ctDNA test is positive, your provider may want you to have imaging tests like CT, MRI, or PET scans. ctDNA testing can help guide whether more treatment is needed, like chemotherapy, after having surgery.
How is ctDNA testing done?
ctDNA testing is done using a blood sample, and sometimes a tissue sample is also taken.
There are a few ctDNA tests commonly used that you may hear about:
- Natera™ has a test called Signatera™.
- Csiro has a test called Colvera™.
- Foundation Medicine has a test called Foundation One® Tracker.
The test you have is based on what your provider recommends for your cancer type and your insurance coverage. If you are unsure about which test you will have, talk to your provider and check to see if your insurance covers the test.
What types of cancer is ctDNA testing used for?
ctDNA testing is still being studied, and it is most often used in colorectal cancer. But, it can be used for other cancer types, like:
The goal of ctDNA testing is to check on your cancer and see how your treatment is working. Ask your providers any questions you have about ctDNA and testing.