A blood test can now detect the presence of 50 different cancers — most of which do not have any other means of screening. The test, the GRAIL Galleri multi-cancer early detection (MCED) test, reports results that include a yes or no readout regarding the presence of a potential cancer, plus the most likely location of the cancer in the body.
A patient with a positive GRAIL test result has about a 55% chance of having a false positive and a 45% chance of having cancer. A positive result should be followed up immediately with diagnostics to determine if cancer is present and if treatment is needed.
The benefits of the test could be early detection for people who are not eligible for screening for breast, prostate, or lung cancer, or detection of cancers that have no screening options, such as pancreatic, liver, and kidney cancer. The test is not yet approved by the U.S. Food and Drug Administration and is not yet covered by health insurance.
Dana-Farber investigators are studying the use of MCED tests to see if they can be a complementary way to screen for cancer.
A blood test can now detect the presence of 50 different cancers — most of which do not have any other means of screening. The test is not yet approved by the U.S. Food and Drug Administration and is not yet covered by health insurance.
Who can receive a MCED test?
MCED tests are being offered directly to consumers: They can be prescribed through a healthcare provider that is familiar with the test or through an online medical consultation. They are available to anyone willing to pay for the test. However, there are some concerns about follow-up care in the case of a positive test.
“The providers that are prescribing these tests via telehealth portals are often not able to perform the work up a patient needs if their test is positive,” says Dana-Farber researcher Catherine Marinac, PhD. “Patients end up seeking help from their local doctors, many of whom are not familiar with these novel tests or what follow-up is appropriate.”
To address this challenge, Marinac and Elizabeth O’Donnell, MD, Director of Early Detection and Prevention of Malignant Conditions at the Dana-Farber Centers for Early Detection and Interception, are launching clinical trials to determine how best to integrate these emerging tests into clinical practice.
“We want to diagnose people early, when curative treatment is more likely to be effective,” says O’Donnell. “But these MCED tests have a lot of implications for clinical practice, so we need clinical trials to determine how best to use these tests in clinical practice.”
Who are MCED tests best for?
Marinac and O’Donnell believe that the best match for MCED tests initially might be patients who are at a high risk of developing cancer at an earlier age than the general population. To explore this idea, they have launched two clinical studies to investigate the use of these tests in people with an elevated risk of cancer.
The INFORM study, led by O’Donnell and Marinac and funded by Dana-Farber Cancer Institute, is working with people with an elevated risk of cancer either due to inherited risk genes or familial risk:
- People over the age of 22 with TP53 mutations (these genetic mutations disable one of the body’s primary means of suppressing tumors).
- People over the age of 35 with other cancer risk genes, such as BRCA mutations or a clinical diagnosis of another cancer predisposition, such as neurofibromatosis, Fanconi Anemia, or Ataxia-Telangiectasia.
- People over the age of 45 with a strong familial risk of cancer.
The study will screen 1,000 people and evaluate the number, types, and stages of cancers detected by the test and will track anxiety and quality of life for people who enroll.
The Sentinel study, led by O’Donnell and Marinac and funded by the U.S. Department of Defense, is working with military veterans, including those:
- Over age 45.
- Who were on active-duty military service for eight or more years.
- Received care at a Veterans Administration facility within the past five years.
“There’s accumulating evidence suggesting that veterans are exposed to carcinogens during military service and have a diverse array of cancers at younger ages,” says Marinac.
This study will screen 1,500 people from this veteran population to evaluate the number of types of cancers detected by the test. The study will also collect information about their service history and potential exposures to learn more.
What are the goals of the studies?
The idea behind these studies is twofold. First, the investigators want to know if MCED tests yield better results for patients. If cancer is detected early and follow-up and treatment are rapid and well-coordinated at a place like Dana-Farber, which specializes in early detection and intervention, will patients have better outcomes than if they had not been diagnosed early?
In particular, the Sentinel study will work with the Department of Defense to create a “synthetic” control group. That is, it won’t enroll people who do not take the test. Rather, the researchers construct a control population of individuals meeting key eligibility criteria in the screening arm, to which the screening group will be compared. The researchers will a matching process to ensure that the control population mimics the characteristics of the group that is being screened with the MCED test.
“This synthetic control will enable us to compare this new type of early screening to standard screening so we can determine if we see evidence of a benefit,” says Marinac. “Will we see a signal that is so strong that it suggests the test is beneficial, or will the signal suggest that the test won’t move the needle in terms of cancer outcomes?”
The second question is whether these tests cause increased anxiety. Taking an MCED test brings the possibility of cancer into sharp focus when, without the test, cancer would just be a vague possibility. Is the benefit of early detection substantial enough to justify the anxiety?