On April 9, Business Insider reported that Galleri, a blood test product developed by Grail—a biotech firm specializing in early-stage cancer detection—has sparked both widespread attention and skepticism over its actual effectiveness. Despite marketing claims that a single blood draw can screen for over 50 types of cancer, multiple large-scale real-world tests have uncovered significant issues, including low early detection rates and high false-negative rates, casting serious doubt on its clinical value.

Supported by the technological prowess of genomics giant Illumina, Galleri was initially highly anticipated by investors. The company went public in 2024 with a valuation of $500 million and applied for U.S. Food and Drug Administration (FDA) approval in January of this year. Currently, a single Galleri test costs between $824 and $950 (approximately RMB 5,630–6,500). The test aims to locate lesions by detecting shed tumor DNA signals in the blood.

However, a 2021 laboratory study revealed that Galleri’s overall cancer detection rate stood at just 51.5%, with the detection rate for stage I early-stage cancer plummeting to a mere 16.8%. Real-world application data has only intensified concerns.

In tests conducted by the San Francisco Firefighters Cancer Prevention Foundation—at a cost exceeding $1 million—only 5 out of 1,786 firefighters tested were diagnosed with advanced-stage cancer, all of whom subsequently died. Meanwhile, the system produced 6 false positives. More alarmingly, at least 3 firefighters with normal test results were diagnosed with cancer within six months. As a result, the foundation announced it no longer supports the routine use of such multi-cancer early detection products.

Large-scale clinical trials worldwide have similarly failed to meet expectations. In a preliminary trial involving 23,000 participants in the U.S. and Canada, Galleri identified 133 cancer cases but missed as many as 196 cases within a year, while generating 83 inconclusive false-positive signals. Furthermore, a 140,000-person trial conducted by Grail in collaboration with the UK’s National Health Service (NHS) failed to achieve its core objective of reducing the number of stage III and IV cancer diagnoses. Following the announcement, Grail’s stock price plummeted by 50%.

Given the limitations of current data, the American Cancer Society currently does not recommend the routine public use of such multi-cancer early detection (MCED) services.