This blood test can detect cancer long before diagnosis
Cancer is the leading cause of death in France, with more than 150,000 deaths per year. Beyond prevention and treatment, diagnosis is a major challenge. The earlier a cancer is detected, the higher the chances of survival. For this reason, many researchers around the world have been trying for years to find new methods to diagnose cancers better and earlier.
Scientists from the renowned American University Johns Hopkins have made their contribution to this project. They have discovered that it is possible to detect cancer in the blood several years before diagnosis, much earlier than previously thought. To achieve this, they analyzed the blood of 52 people using "highly precise and sensitive sequencing techniques," they explain in a press release.
Of the people studied, half were diagnosed with cancer within 6 months of the blood sample being taken, and the other half were not. Blood samples taken more than 3 years before diagnosis were also studied in some of the cancer patients.
The researchers were then able to detect "genetic material released by tumors" in blood taken more than three years before diagnosis. This test is "promising for detecting cancers at a very early stage," says oncology professor Bert Vogelstein, one of the lead authors of the study published in the journal Cancer Discovery on May 22, 2025.
This test, if proven effective in detecting cancers very early in larger studies, represents immense hope. "Three years earlier, we have time to intervene. The tumors are probably much less advanced and more likely to be cured," hopes the study's lead author, Yuxuan Wang, assistant professor of oncology at the Johns Hopkins University School of Medicine. This test, called MCED for "multicancer early detection," is, as its name suggests, capable of detecting dozens of different cancers even before symptoms appear.
L'Internaute
