What it reads. Cancer cells die faster than healthy ones and leak DNA fragments into the bloodstream. The test reads the chemical tags on those fragments, spots a shared cancer signal across fifty-plus tumour types, and names the one or two body sites most likely to be the source ¹. It works best when there's plenty of cancer to find: sensitivity runs about 17% at stage I and 90% at stage IV ¹.

The case for it. Two thirds of US cancer deaths come from cancers with no recommended screen ². This is the first tool aimed at that gap. In the biggest healthy-adult trial, roughly three early-stage cancers were caught per thousand people screened, and a positive result was truly cancer about 62% of the time ³.

The case against it. The world's first randomised trial, in 142,250 UK adults, missed its main goal in June 2026. Late-stage diagnoses across all cancers didn't fall meaningfully. In the twelve deadliest, stage IV diagnoses dropped 22–26% and early catches rose 16%, but whether that saves lives won't be known until around 2030 ⁴.

This is an add-on, not a replacement. The question is never this instead of your colonoscopy — it's whether to layer it on top, at your own cost, for a shot at a cancer nothing else screens for.

What a good outcome looks like. For the rare person whose test catches an early version of a deadly cancer, the swing is large: pancreatic cancer at stage I runs about 40% five-year survival versus 3% at stage IV; ovarian, roughly 90% versus 30%. For the other 996 in 1,000 screened in a year, the result is reassurance, a false-alarm scare, or nothing. A negative doesn't change a thing you were already going to do.