The Galleri test

What the Galleri test is

Cancers shed tiny fragments of DNA into the blood. The pattern of chemical tags on that DNA looks different from healthy cells. The Galleri test reads those patterns from one ordinary blood sample. If it finds a cancer signal, it also predicts where in the body the signal is most likely coming from, which tells the doctor where to look next.

It is made by GRAIL and processed in a laboratory accredited to ISO 15189, CAP and CLIA. The test carries a UKCA mark. It is a private test; it is not part of NHS screening.

What it can do

• Look for cancers that have no screening programme. The UK screens for breast, bowel and cervical cancer, and offers a targeted lung scan to people at high risk. That leaves most cancer types with no routine test at all. Galleri looks across more than fifty of them in one go.

• Point to where a signal is coming from. When the test finds a signal, it predicts the origin correctly around nine times in ten, so the follow-up is focused rather than a scramble of scans.

• Keep false alarms low. A positive result is uncommon, and when it happens it is right more often than not. In the large NHS trial, around half of people with a positive test were found to have cancer.

What it cannot do

We would rather you knew this before you booked than after.

• A clear result does not mean you are cancer-free. The test misses more cancers than it finds, particularly early-stage ones. In the large NHS trial it picked up roughly a third of the cancers that were diagnosed within a year. A negative Galleri result is reassuring, not a guarantee.

• It does not replace NHS screening. If you are due a mammogram, a bowel-screening kit, a smear or a lung scan, have those. Galleri sits alongside them, it does not stand in for them.

• It does not investigate symptoms. If something is worrying you, a doctor's appointment is the right front door, not this test.

• The survival benefit is still being proven. The technology clearly works at detecting cancer signals. Whether finding cancer this way makes people live longer is not yet proven, and we say so plainly below.

Where the evidence stands

We think you should have the full picture before you decide.

The largest study of Galleri is the NHS-Galleri trial: 140,000 people aged 50 to 77, results reported in 2026. The test performed well at what it is designed to do, and there were encouraging signals in the later rounds of screening. Its main goal was to show that adding Galleri to normal care cut the number of cancers caught late, at stage III or IV, over three years, and on that headline target it fell short. Data on whether it helps people live longer is still a couple of years away.

The independent expert view is broadly this: the technology genuinely detects cancer signals, sometimes early, with few false alarms; it is not yet proven enough to roll out to the whole population; and it should be used as a supplement to existing screening, not a replacement.

So this is an early-detection test with real strengths and real limits. For some people it is a sensible extra layer. For others it will add worry and cost without adding much. The consultation exists to work out which you are.

Who it suits

Galleri tends to make most sense for adults from around 50, and for younger adults with a family history or other reason to be watchful, who are already keeping up with NHS screening and want to look wider than the programmes cover. It is a considered choice, not a routine one.

It is a poor fit if you have symptoms you have not had checked, if you are looking for reassurance that would be better answered by keeping up with standard screening, or if a positive result you could not act on would cause you more harm than the test could offer. We will talk all of this through before you spend anything.

Price

£1,300 all in if you go ahead: the consultation, the test and your doctor's review of the result.

The consultation is £120. Go ahead with the test and that £120 is part of the £1,300, with nothing added for the consultation. If the test is not right for you, or you decide not to proceed, you pay only the £120 for the consultation.

For an in-person consultation you pay afterwards. For a video or phone consultation the £120 is taken when you book.