Despite significant advancements in cancer treatment and prevention, cancer is expected to claim nearly 610,000 American lives in 2023 according to this year’s report from the American Cancer Society (ACS). The report highlighted that while overall cancer deaths are falling, death rates from some cancers and among certain at-risk populations have remained stable or have increased.
Trends in overall cancer incidence and mortality provide a window into how well we’re preventing, detecting and treating cancer in the U.S. This year’s ACS report underscores cancer screening as a vital tool in the war on cancer and shows why there is an urgent need to implement new approaches to screen asymptomatic people at-risk (e.g., those over the age of 50). The Biden Cancer Moonshot also underscores the need to greatly expand the number of cancer types we screen for to detect and diagnose more cancers earlier.
Despite 50 years of the “war on cancer” and research into cancer screening, most cancers are still detected too late, after a person develops symptoms and once the cancer has already spread. This is because the currently recommended screening tests only find 15% of the total cancer burden among those eligible for screening. Recommended screening tests can find cancer early and improve outcomes, but are only available for three types of cancers for women and two for men, with an additional screen for heavy smokers. We know that cancer found in an early stage is generally associated with improved survival versus cancer found in later stages, which can be more difficult and costly to treat and may have fewer therapeutic options. In fact, the 5-year survival rate across all cancers is 89% when cancer is found while it is still localized, but drops to 21% once it’s spread. Screening for one cancer at a time—and for so few cancers—is simply not going to materially reduce deaths from cancer, as most cancers are totally uncovered by the current screening paradigm.
To make a meaningful reduction in overall cancer deaths, we need a new, population-scale approach for screening people that finds many more cancers before symptoms appear, and in earlier stages, when outcomes are more likely to be favorable. This approach is rooted in the fact that any person is at measurable risk of any of hundreds of types of cancer, and that person does not get to choose what type of cancer they get. In fact, an individual having a colonoscopy has ten times higher risk of cancer other than colorectal, illustrating the limitations of the single cancer screening approach. Furthermore, screening for cancers one at a time causes false positive tests and unnecessary workups to be accumulated with every distinct test. Thus, screening for each cancer type one at a time is not sensible, scalable or efficient. A new screening paradigm must be implemented to maximize the benefits of early detection and minimize potential harms, including false positives, overdiagnosis and healthcare system burden.
The genomic revolution has provided new tools and the ability to assess biological features of cancer by simply looking in the blood. A novel approach including multi-cancer early detection (MCED) is the best chance to address the growing burden of late-stage cancer in an aging population and potentially bend the cancer mortality curve.
MCED uses liquid biopsy with genomic technology, and couples them to machine learning to detect cancer signals in DNA circulating in the blood. When added to standard screening, MCED technologies can identify a broad range of cancers that aren’t screened for today, often before they become symptomatic or spread. Clinical modeling shows MCED testing has the potential to prevent more than a quarter of all cancer-related deaths expected within five years of diagnosis.
The Galleri® test from GRAIL, available by prescription, is the first clinically validated MCED test that, using a simple blood draw, can detect a shared cancer signal across more than 50 types of cancers. In a recent study, Galleri demonstrated a very low false positive rate (less than 1%) and predicted where in the body the cancer signal came from with 89% accuracy. The test offers a fundamentally different blood-based approach intended to complement—not replace—recommended single cancer screenings.
The ability to identify the location of the cancer signal is critical for any MCED test, to target the physician’s diagnostic evaluation. MCED identifies a cancer signal but does not diagnose cancer, so identification of where in the body the cancer signal came from can result in an efficient and targeted evaluation, avoiding unnecessary tests, radiation and costs. A recent study found that when patients had cancer, the test’s prediction of location led to resolution of the cancer diagnosis in less than three months for most participants, and in less than two months for half of them. Delays in confirming a diagnosis can cause anxiety and frustration for both patients and physicians.
Developing more single cancer screening tests is not the answer. Even if recommended single screening tests were available for every individual cancer type, administering these on a mass scale would be impractical, inefficient, cost-prohibitive and would overwhelm the healthcare system with false positive test results. Right now, an individual who receives all the recommended single-cancer screening tests in a year would have a cumulative false-positive rate of 31% for men and 43% for women. MCED tests can detect 50 or more cancer types by finding a shared signal with a false positive rate of 0.5%, a tremendous advantage.
The ACS report shows progress, yet far too many Americans are expected to die from cancer. Asymptomatic and earlier detection offers the best chance to meaningfully reduce these numbers. Expanding our cancer screening paradigm to include MCED tests represents a new front in the war on cancer and may help us finally win the war.
Important Galleri Safety Information
The Galleri test is recommended for use in adults with an elevated risk for cancer, such as those aged 50 or older. The Galleri test does not detect all cancers and should be used in addition to routine cancer screening tests recommended by a healthcare provider. Galleri is intended to detect cancer signals and predict where in the body the cancer signal is located. Use of Galleri is not recommended in individuals who are pregnant, 21 years old or younger, or undergoing active cancer treatment.
Results should be interpreted by a healthcare provider in the context of medical history, clinical signs and symptoms. A test result of “Cancer Signal Not Detected” does not rule out cancer. A test result of “Cancer Signal Detected” requires confirmatory diagnostic evaluation by medically established procedures (e.g., imaging) to confirm cancer.
If cancer is not confirmed with further testing, it could mean that cancer is not present or testing was insufficient to detect cancer, including due to the cancer being located in a different part of the body. False-positive (a cancer signal detected when cancer is not present) and false-negative (a cancer signal not detected when cancer is present) test results do occur. Rx only.
GRAIL’s clinical laboratory is certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA) and accredited by the College of American Pathologists. The Galleri test was developed, and its performance characteristics were determined by GRAIL. The Galleri test has not been cleared or approved by the U.S. Food and Drug Administration. GRAIL’s clinical laboratory is regulated under CLIA to perform high-complexity testing. The Galleri test is intended for clinical purposes.