Multi-cancer early detection blood tests: what to know
Multi-cancer early detection (MCED) tests, also called multi-cancer detection (MCD) tests, look for signs of many kinds of cancer in one blood sample, such as bits of DNA shed by cancer cells. They are new, they do not diagnose cancer, and they do not replace the screenings you are due for. (ACS, 2025) (NCI) Your doctor decides with you whether one makes sense.
Where things stand
| Question | Status |
|---|---|
| FDA approval | None cleared or approved. Some are offered as lab-developed tests, which a doctor can order. The rules for these tests do not require proof that they help patients. (ACS, 2025) (NCI) |
| FDA review of Galleri | An FDA advisory panel met on September 23, 2026. It voted 10 to 0 on safety, 6 to 4 on effectiveness and 7 to 2, with 1 abstaining, that benefits outweigh risks for adults 50 and older. The FDA makes the final decision. (FDA panel, 2026) |
| USPSTF and medical societies | No recommendation on using these tests for screening. (NCI) The American Cancer Society says there are no US clinical practice guidelines for them yet. (ACS, 2025) |
| Proof of fewer cancer deaths | Not yet known. (ACS, 2025) The NCI is running the Vanguard pilot study of two other tests in up to 24,000 adults aged 45 to 75 to plan a larger trial. (NCI, 2025) |
| Cost | Most people pay out of pocket: several hundred dollars, according to the American Cancer Society, or around $900, according to the NCI. Follow-up tests after a positive result may also cost money. (ACS, 2025) (NCI) |
| Medicare | Not covered yet. A law signed on February 3, 2026 gives Medicare a path to cover these tests once one is FDA approved and shown to have clinical benefit. Medicare sets the coverage details, and the tests are meant to add to existing screening, not replace it. (Rep. Sewell, 2026) |
Where they differ: most of the FDA advisory panel found that Galleri's benefits outweigh its risks, especially for cancers that have no screening test. (FDA panel, 2026) The NCI says it is not yet known whether the tests now sold are more likely to help or harm, and that randomized trials are needed. (NCI) The American Cancer Society says more research is needed before they can be recommended for wide use. (ACS, 2025)
What a "cancer signal detected" result means
- A positive result is a signal that cancer might be present, not a diagnosis. Some tests also suggest where in the body the signal comes from. (NCI)
- More tests follow, which may include blood tests, scans and a biopsy. Doctors do not yet know the best order of tests, or what to do if they find no cancer. (NCI) (ACS, 2025)
- In PATHFINDER, a US study of 6,621 adults 50 and older, 92 (1.4%) had a cancer signal. 35 of them (38%) were diagnosed with cancer and 57 (62%) were not. Most people in both groups had imaging. Finding out took a median of 79 days, and 162 days for people who turned out not to have cancer. (PATHFINDER, 2023)
- In the NHS-Galleri trial, the predicted place of origin was right in about 91% to 94% of people found to have cancer. (Nat Med, 2026)
- A test may also find slow-growing cancers that would never have caused harm. (NCI) See false positives and overdiagnosis.
What the NHS-Galleri trial found
The NHS-Galleri trial in England randomly assigned 142,250 people aged 50 to 77 to have the Galleri test once a year for three years, or not, on top of usual care. (Nat Med, 2026) It is the largest trial of a multi-cancer blood test so far. Both PATHFINDER and NHS-Galleri were funded by the company that makes the test. (Nat Med, 2026) (PATHFINDER, 2023)
| Measure | Result |
|---|---|
| Got a positive result | 0.91%, about 1 in 100 |
| Positive and diagnosed with cancer | 52.0%, about half |
| People with cancer who got a positive result | 30.7%, about 1 in 3 |
| People without cancer who got a negative result | 99.55% |
| False alarms | 0.45% of the time |
Source for the table: (NHS-Galleri, 2026) The published paper reports results for each of the three yearly rounds, with similar figures. (Nat Med, 2026)
- The main goal was fewer late-stage (stage 3 and 4) cancers. There was no difference, so the trial did not meet its main goal. (NHS-Galleri, 2026) (Nat Med, 2026)
- In 12 fast-growing cancer types the researchers looked at first, there were 14% fewer stage 4 cancers and 16% more stage 1 and 2 cancers in the tested group. Researchers will look again with 12 more months of data, and it is not yet known whether the test reduces cancer deaths. (NHS-Galleri, 2026)
- About 2 in 3 cancers diagnosed in the tested group were not flagged by the test. A negative result does not rule out cancer. (NHS-Galleri, 2026) (FDA panel, 2026)
Why your usual screenings still matter
Proven screening tests exist for breast, cervical, colorectal, lung and prostate cancer, and some, like colonoscopy and Pap tests, can find changes before they become cancer. (ACS, 2025) (NCI) A multi-cancer test does not replace any of them, and a negative result is no reason to skip one. (ACS, 2025) (FDA panel, 2026) Guidance written for family doctors on behalf of the American Cancer Society says doctors do not have to raise these tests, but should talk them through with people who ask, and use the visit to help them get the screenings they are due for. (Cancer, 2025) See which ones apply to you in cancer screenings by age.
If you are thinking about one, the American Cancer Society suggests asking: Would I be a good candidate? What does it cost, and will my insurance cover it? What are the possible benefits, limits and harms? How often would I need it? (ACS, 2025) If you would not want more tests after a positive result, the test may not suit you. (ACS, 2025) More on shared decision-making.
Do not ignore new symptoms, whatever any test result says. See your doctor about them. (ACS, 2025)
Questions people ask
Is a multi-cancer blood test FDA approved?
Not as of October 30, 2026. No multi-cancer test has been cleared or approved by the FDA. Some are sold as lab-developed tests that a doctor can order. An FDA advisory panel reviewed the Galleri test on September 23, 2026 and voted 7 to 2, with 1 abstaining, that its benefits outweigh its risks; the FDA itself makes the final decision. (ACS, 2025) (NCI) (FDA panel, 2026)
Does a multi-cancer blood test replace a mammogram or colonoscopy?
No. The American Cancer Society, the NCI and the FDA advisory panel all say these tests do not replace recommended screening for breast, cervical, colorectal, lung and prostate cancer. (ACS, 2025) (NCI) (FDA panel, 2026)
What does "cancer signal detected" mean?
It means the test found a pattern that may come from cancer. It is not a diagnosis. More tests, such as scans and sometimes a biopsy, are needed to find out if cancer is there. In the NHS-Galleri trial about half of the people with a positive result were diagnosed with cancer. (NCI) (NHS-Galleri, 2026)
If my multi-cancer test is negative, can I skip screening?
No. In the NHS-Galleri trial the test found about a third of the cancers that were diagnosed, so most cancers were not flagged. Keep up your recommended screenings and tell your doctor about new symptoms. (NHS-Galleri, 2026) (ACS, 2025)
Does Medicare pay for a multi-cancer blood test?
Not yet. A law signed in February 2026 creates a path for Medicare to cover these tests once one is FDA approved and shown to have clinical benefit, with Medicare setting the details. Until then most people pay out of pocket. (Rep. Sewell, 2026) (ACS, 2025)