Researchers at the University of Oxford have developed a blood test capable of detecting multiple types of cancer up to five years before clinical symptoms appear, in what leading oncologists are calling the most significant advance in cancer diagnostics in a generation.

The test, which analyses patterns of cell-free DNA fragments in the bloodstream, demonstrated 93 per cent sensitivity across 12 common cancer types in a clinical trial involving 25,000 participants. False positive rates were below 1 per cent.

"Early detection is the single most important factor in cancer survival," said Professor Sarah Chen, who led the research. "This test could fundamentally change the equation — catching cancers when they are small, localised, and curable rather than large, metastatic, and lethal."

The NHS has announced a fast-track evaluation programme, with the test potentially available through the national screening programme within three years. At an estimated cost of £200 per test, it would represent a fraction of the expense of treating late-stage cancers.

Cancer Research UK described the results as "extraordinarily promising" while cautioning that further validation in diverse populations is needed before widespread deployment. The research was published simultaneously in Nature Medicine and The Lancet Oncology.