Emerging technology Seeking to help revolutionize the world of cancer diagnosis: Multiple Cancer Early Detection (MCED) tests aim to detect signals specific to different types of cancer through a single blood draw or other body fluid sample. Also known as a specific type of Liquid biopsyMCED tests look for abnormalities that may indicate cancer, such as Circulating tumor DNA; Some tests can indicate the possible origin of cancer, while others may only show the possibility that cancer is present Without specifying the type or possible location.
key feature Proponents say that one of the most important of these factors is its ability to identify cancer at earlier, more treatable stages. As such, they may help save life.
Industry tests show some promise: in simulation model Research funded by Exact Sciences—a Wisconsin-based company that developed an MCED called Cancerguard—supplemental MCED testing led to an increase in stage I, II, and III diagnoses (by 10, 20, and 34 percent, respectively). Meanwhile, stage IV diagnoses have dropped by nearly half. The authors – some of whom are listed as employees of Exact Sciences – suggested that this shows that the MCED test can detect cancer before it reaches its most advanced stages, especially for types of cancer that lack routine screening.
But while some doctors say the tests are useful for people at a young age High riskSome researchers have expressed concern about routine use before Asymptomatic Individuals without clear risk factors can lead to unnecessary tests and procedures.
For example, Gilbert Welch, MD, an experienced internist and researcher at the Center for Surgery and Public Health at Brigham and Women’s Hospital. expert On cancer screening, he emphasizes that different types of scans, including MCEDs, can detect dormant cancers that rarely cause symptoms or death. This, in turn, may lead to unnecessary treatments, increased health care costs, and patient anxiety. And an Australian researcher as well Refers to Breast and thyroid cancer are overdiagnosed. At least one simulation model, discussed below, suggests that the risk of overdiagnosis is relatively low.
MCEDs may also be Less sensitive In detecting cancer at an early stage, compared to other organ-specific cancer tests, which raises the eyebrows Questions On whether MCED screening actually results in patients living longer. Sensitivity rates — the rate at which a test accurately detects cancer — It could be Low like About 20 percentAlthough they are vary widely Depending on the type of cancer and the specific test it has spread.
Could more screening turn mainly healthy people — sometimes called “the anxious well” — into sick people? This is possible.
MCED tests, though, have High privacyor the test’s ability to correctly identify people who do not have cancer. But when screening a large, mostly healthy population, even a highly specific test can generate many false positive results. This, in turn, can lead to what doctors call a “diagnostic odyssey,” which involves additional blood tests, scans, and biopsies to make a proper diagnosis. In one year 2023 He studies62% of the positive results were false as the cancer was not found after extensive testing.
Maybe more Examination Then they turn mainly to healthy people – they are sometimes called “Well worried” – In patients? It’s possible. The late University of Pennsylvania medical professor William Kasich once said books“A healthy individual can be defined as someone who has not been adequately studied.” This adage is consistent with the idea that One seems harder For disease, the higher the incidence of disease.
Multiple cancer early detection tests have not yet been approved by the Food and Drug Administration, but are commercially available to consumers who have them A prescription From a qualified health care provider. The Gallery test is one notable example. The product’s manufacturer, Grail, says the test can screen for more than 50 types of cancer for a list price of $1,000. $949. The cup says it is sold 185,000 tests In 2025. While most health insurance companies Not currently covered Diagnostics, more could start paying for it if the FDA allows its use. (In January, Grill applied for FDA approval.)
Cancerguard of exact sciences is Similar MCED This is also on the market in the US and this year, California-based Guardant Health Fired A test to detect multiple cancers is called Shield, not to be confused with the company’s test Colon cancer screening A tool with the same name, in Asia but not yet in the United States.
Proponents say MCEDs have the potential to identify cancer at earlier, more treatable stages, thus saving lives. However, to date, the marketing of commercially available MCEDs is far ahead of the science.
Contrary to some expert concerns, a recently published model that includes MCEDs, which has not yet been peer-reviewed, suggests that these tests have a relative impact. Low risk Of overdiagnosis Researchers have investigated possible indolent cancers that progress slowly and usually remain undiagnosed without screening. They found that between 2 and 6 percent of all cancers detected annually using MCED could be overdiagnosed, although the risk increases strongly as a person ages.
But these results came from simulation; The study did not include real people. Offline multiplayer studies To evaluate MCEDs involving trial participants is ongoing. It arrives (Real-World Evidence to Promote Health Equity in Early Detection of Multicancer) for example, is a prospective study enrolling nearly 50,000 Medicare beneficiaries in the United States to evaluate whether adding GALLERY to usual care impacts early cancer detection and reduces late-stage diagnoses. The study was sponsored by GRIL.
The gold standard for evaluating cancer screening programs would be an independent randomized controlled clinical trial. British National Health Service He studies From Cannes Gallery Firstly Of its kind involving MCED. In the United Kingdom, before any new national multiple cancer screening program is launched, clinical trials of this type are being undertaken Need to show The use of MCEDs leads to fewer deaths from cancer due to Previous diagnoses. However, gallery Did not meet The primary endpoint of the NHS trial was a reduction in diagnosis in later stages of cancer.
However, the manufacturer tested press release The results indicate a “positive trend toward fewer stage III-IV cancers” for 12 types, including lung, pancreatic, colorectal and ovarian cancers.
“It’s a very tempting prospect that you could do just one blood test and find all types of cancer.”
– Andrew Vickers, Memorial Sloan Kettering Cancer Center
In an email, Welsh posited that detecting tumor DNA “may be clinically useful as a diagnostic test,” and may be useful to doctors deciding, for example, whether a colon cancer patient who has already undergone surgery needs further treatment. But he stresses that the diagnosis should not be rolled out as a “screening test in the general population.”
“It’s a very enticing prospect that you could do just one blood test and find all cancers” because it means you don’t need to test for one type of cancer at a time, like a mammogram, colonoscopy, or lung CT scan, Andrew Vickers, a biostatistician at Memorial Sloan Kettering Cancer Center, wrote in an email. But Vickers cautioned: “We should only use tests if they are proven to work.”
He added that the problem with MCEDs is that they have not even been proven to be able to detect cancers with appropriate sensitivity and specificity, or save lives. The last one failed exam From Gallery Explaining the issue at hand, Vickers wrote: “I have a big problem with companies advertising expensive, unproven tests to the public.”
In response to such criticism, a Grill spokesperson provided a response that stands by the company’s product, noting its ability to screen for many different types of cancer, “including hard-to-detect cancers such as pancreatic, ovarian, and liver cancer, before they develop symptoms.”
Regarding the recent failed test, the response noted that although “there was no significant reduction in the pooled primary endpoint of stage III and IV cancers, the trial generated strong evidence that the Gallery test can increase early cancer detection and reduce stage IV metastatic disease on a population-wide basis.”
When asked for comment by this author, Tom Beer, chief medical officer for early detection of multiple cancers at Abbott (which acquired Exact Sciences in March of this year), wrote:
“Cancerguard was intentionally designed with a high specificity and direct imaging-based diagnostic pathway to help reduce unnecessary procedures while enabling early detection of cancers that are currently unscreened for.” While Abbott respects “the debate around early detection of multiple cancers, including questions about overdiagnosis and responsible introduction of these technologies,” Beer noted that given “the scale of cancer deaths today, we believe it is reasonable and responsible to continue developing these technologies while rigorously considering their long-term impact.”
Stephen Woloshin, professor of health policy and clinical practice at Dartmouth Geisel School of Medicine, stressed that the public needs to know whether the benefits outweigh the harms. In this context, he cited Muir Gray, a British physician and famous public health expert, who stated that “all screening programs do harm; some also do good, and some do more harm than good at a reasonable cost.”
Ultimately, it may take time to evaluate the clinical benefit of MCEDs Years. Accordingly, MCEDs It may be years It is ready for widespread use. If so, it is important for those considering their use in the meantime to consider both the potential benefit of early detection and the potential harms associated with overdiagnosis, false positives, and unproven ability to save lives.
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