There has been a lot of hype around Galleri, the blood test that claims to detect more than 50 cancers. The test isn’t approved by the FDA yet, but in 2025, more than 185,000 were sold to consumers for $949 each. Insurance does not pay for them as they are not FDA-approved. Now, a clinical trial has found that using the test didn’t reduce Stage III and IV cancer diagnoses over three years.
Galleri is one of about 40 multi-cancer early detection (MCED) tests available or in development. But it’s the first to be through such a public trial.
Cancer geneticist Dr. Richard Houlston said the results show Galleri is “not a very good test.” He also said, “This doesn’t support rollout within the American health care system.”
“When you get a negative test, that’s nice, but you could still be harbouring cancer,” said Dr. Eric Topol, a physician-researcher and founder of the Scripps Research Translational Institute. “I think it’s just irresponsible to promote these tests with the data we’ve seen so far.”
However, others argue that three years isn’t a long enough time frame for the study. And, detecting cancer early may not be the best use of the tool, according to some experts. If it can spot slow-growing cancers, the test could prevent overdiagnosis, cost and anxiety.
“I would hope that these results do not dampen enthusiasm for what is potentially a paradigm-shifting approach to cancer screening,” said Dr. Richard Hoffman. “These tests are continually evolving to improve their diagnostic accuracy and may find a better niche by limiting the number of tested cancers, targeting high-risk populations and being used for cancer surveillance.”
The study found that using the Galleri test reduced the number of cancer cases being diagnosed through emergent situations. Cancers discovered because they have urgent symptoms are often more expensive to treat and more fatal. Combining standard screening and Galleri led to four times better detection rates of breast, colorectal, cervical and high-risk lung cancer. Galleri increased the diagnosis rate for 12 different deadly cancers when they were Stage I and II. The 12 cancers are usually found later, when they are harder to fight.
Another MCED test, Cancerguard, costs $689. It also detects 50 types of cancer. But it can give false-positives and the company’s Chief Medical Officer, Thomasz Beer, said the test should be used with traditional tests, not as a replacement.
Looking at how these tests started and how far they have come, it’s possible that they are the future of diagnostic medicine in cancer care. But, at this point, they do not replace regular trips to the doctor and traditional screening. Using an MCED test without having a conversation with your doctor isn’t advisable. It’s not just expensive; it may give you less information than you would expect.
