Multi-cancer blood test shows promise in NHS study

Posted on the 5th June 2023

A pioneering blood test that uses changes in genetic code to screen for more than 50 types of cancer could accelerate diagnosis and fast-track patient treatment.

The Galleri blood test detects tiny fragments of tumour DNA in patients’ bloodstreams, can alert doctors as to whether a cancer signal has been detected, and can even predict where in the body the signal originated.

Led by the University of Oxford, the SYMPLIFY study enrolled 5,461 patients in England and Wales whose GPs had referred them to hospital with suspected cancer.

The test correctly identified two-thirds of cancers among the study’s participants and, in 85% of cases, was able to pinpoint the original site of the disease. More than 350 of the study’s participants subsequently had their diagnosis confirmed via traditional methods, such as biopsies and scans.

With a particularly high accuracy rate among older patients and those with advanced cancers, the liquid biopsy test proved especially adept at identifying hard-to-spot cancers, including throat, bowel, lung, pancreatic, and head and neck cancers.

The trial results were published at the world’s largest cancer conference, the American Society of Clinical Oncology’s annual meeting in Chicago.

While the Oxford researchers stress that the test remains a ‘work in progress’ that is not accurate enough to ‘rule in or rule out cancer’, they are optimistic that the test could go on to aid GPs in clinical assessments, facilitating faster diagnosis for those with cancer and faster reassurance for those without the disease.

Lead researcher and professor of experimental cancer medicine, Mark Middleton, stresses that the test has ‘potential for identifying people going to see their GP who are currently not referred urgently to investigate cancer … who do need testing’.

Prof Nicholas Turner, of the Institute of Cancer Research in London, welcomed the valuable potential data provided by the study: ‘It could well be useful in the future to fast-track patients into rapid-access clinics, and especially in people where imaging findings are uncertain.’

The NHS has also been using the Galleri test in thousands of asymptomatic patients to assess whether it can detect hidden cancers. Results are expected later this year.