Why is cancer monitoring important?
When someone has been treated for cancer, there are several monitoring tools doctors use to detect cancer remaining in the body. Knowing if there are traces of cancer present, can help the doctor or oncologist decide:
How the patient is responding to treatment
If further cancer treatment needs to be considered
Whether there are signs that the cancer has returned or progressed
The most common imaging tools used to detect the presence of cancer are computerized tomography (CT) scan, magnetic resonance imaging (MRI), positron emission tomography (PET) scan, mammography, and X-ray. However, these imaging tools are limited in their ability to detect very small traces of cancer in the blood called molecular residual disease (MRD). If left untreated, residual cancer cells are highly likely to multiply and cause a recurrence.
Molecular residual disease is the presence of small traces of cancer in the blood, such as circulating tumor DNA (ctDNA) or microscopic pieces of tumor DNA.
Signatera is a new cancer monitoring test that is personalized for each patient
Signatera is a custom-designed test generated based on each patient’s unique set of tumor mutations.
Knowing earlier if your cancer is likely to recur or has progressed after treatment can help you have a more informed discussion with your doctor on how to continue to treat or monitor your disease.
How is the Signatera test performed?
1. Analysis to determine your unique set of tumor mutations
The DNA sequence from your tumor tissue and normal cells from your blood are compared to determine the unique set of mutations specific to your tumor tissue. This process happens only once.
2. Custom-designed and personalized for you
The next step of the Signatera process is to select 16 tumor DNA mutations that occurred early in your cancer’s origination. These mutations are called “clonal mutations” and would also be present in all future cancer cells. The clonal mutation selection process happens only once.
3. Signatera test detects presence or absence of tumor DNA
Once your personalized Signatera test is created, it can be used to detect the presence or absence of tumor DNA from any future blood samples.
How long will it take to receive the Signatera test results?
The first time the Signatera test is ordered, it will take 2 weeks for tumor
tissue sequencing results to become available from the date the tumor tissue is received. Then, it will take another 2 weeks for your personalized test design and for your physician to receive the first Signatera test result
After the test has been designed, it will take 1 to 2 weeks for your Signatera test results to become available after your blood sample is received by the Natera laboratory
What do the Signatera test results mean?
Your test result will either be positive or negative for the presence of tumor DNA in your blood. Your doctor will receive the test report and then will be able to discuss your results and answer questions.
A positive Signatera test result indicates that tumor DNA has been detected in your blood.
A positive result means there is higher risk for your cancer returning. Consult your doctor or oncologist to discuss additional options for cancer monitoring or treatment.
Prior to receiving your treatment, you are likely to have a positive result. Your doctor may monitor for changes in ctDNA levels to monitor your tumor’s response to treatment.
A negative Signatera test result indicates that tumor DNA was NOT detected in your blood
A negative result means that you are more likely to remain cancer-free.
A negative result after your treatment may mean that the therapy was able to decrease the amount of cancer cells to levels undetectable to the Signatera test.
No test is perfect, and negative results may change over time. A negative Signatera result doesn’t guarantee that tumor DNA was not in your blood, nor that it will never be detected in the future. That is why the Signatera test is recommended for periodic use over the course of your cancer care as directed by your doctor, to detect changes in the presence or absence of tumor DNA.
Limitations of the test: While the Signatera test is highly sensitive and specific, no screening test is 100% accurate in predicting cancer progression status. A negative Signatera test result does not guarantee your cancer is cured or that you will remain cancer-free forever. A positive Signatera test result also does not indicate that every patient will have a recurrence of cancer. Signatera is not designed to detect ctDNA in patients with more than one primary cancer, provide treatment selection guidance, or test for hereditary cancer syndromes.
How accurate is the Signatera molecular monitoring test?
Signatera has been studied in clinical studies across multiple solid cancer tumor types including colon, breast, lung, and bladder.
Signatera can detect extremely small amounts of tumor DNA before cancer recurrence can be seen by traditional imaging tools such as CT scans or MRI.2-5 The Signatera test is highly sensitive and specific, meaning that if your test result is positive, there is a high likelihood that your cancer may recur without further treatment. The test’s ability to correctly identify the presence of molecular residual disease (MRD), is what makes Signatera unique.
When should the Signatera test be considered?
At initial cancer diagnosis, to establish a baseline before surgery or treatment
After surgery, before starting chemotherapy
During treatment, to evaluate treatment response
After treatment, to monitor for molecular residual disease or tumor response to treatment
This test can only be ordered by a licensed oncologist or doctor treating your cancer. Talk to your doctor to see if you may be a candidate for the Signatera test.
Leading cancer centers around the world are using the Signatera test in their studies
Signatera is used extensively in research studies with leading cancer academic centers, including Aarhus University, Cancer Research UK, Columbia University, Fox Chase Cancer Center, Imperial College of London, Institut Jules Bordet, UC San Francisco, University of Leicester, and Vanderbilt University.