The NHS has launched the world’s largest trial of a new blood test that can detect more than 50 types of cancer before symptoms appear.
The test has been shown to be particularly effective at finding cancers that are typically difficult to identify early – such as head and neck, bowel, lung, pancreatic, and throat cancers.
The Galleri™ test works by finding chemical changes in fragments of genetic code – cell-free DNA (cfDNA) – that leak from tumours into the bloodstream.
The trial aims to recruit 140,000 volunteers in eight areas of England. Participants, from different backgrounds and ethnicities and aged between 50 and 77, must not have had a cancer diagnosis in the last three years. They will be asked to give a blood sample at a locally based mobile clinic and they will then be invited back after 12 months, and again at two years, to give further samples.
The trial is part of the NHS’s efforts to increase the proportion of cancers detected early by the end of the Long Term Plan. A patient whose cancer is diagnosed at stage one or two typically has between five and 10 times the chance of surviving compared with those found at stage four.
Initial results of the study are expected by 2023 and, if successful, the NHS in England plans to extend the rollout to a further one million people in 2024 and 2025.