A simple, cheap test can help identify who is at risk of developing colorectal cancer, new research suggests.

Scientists say this could aid early diagnosis and potentially save lives.

The study found the faecal immunochemical test (FIT), which costs around £4, can pick up traces of hidden blood in faeces.

Researchers said it performs well in patients with low-risk symptoms to quickly and accurately identify who is likely to not have colorectal cancer, and who should be referred for investigation.

Led by the University of Exeter, and supported by the Peninsula and the Somerset, Wiltshire, Avon, and Gloucestershire Cancer Alliances, and by the Cancer Research UK CanTest Collaborative, the study examined data from almost 4,000 patients aged 50 and over.

The study involved all healthcare providers in the south-west of England.

Over six months, the test was given to anyone with low-risk symptoms of colorectal cancer – that is, symptoms that can be caused by bowel cancer but are also very often caused by other things.

These include things such as stomach ache, unexplained weight loss, or anaemia.

Prior to this, there was no easy-to-do test available for people with low-risk symptoms of colorectal cancer.

From June to December 2018, 3,890 patients received the FIT.

Of those, 618 tested positive for blood in their faeces, 43 of whom had received a diagnosis of colorectal cancer within 12 months.

In the group that tested negative, only eight were diagnosed with colorectal cancer a year later, according to the study published in the British Journal of Cancer.

Dr Sarah Bailey, from the University of Exeter Medical School, who led the study, said: “Our findings are very exciting – we show that this simple and inexpensive test performs exceptionally well in this group of patients with low-risk symptoms, to quickly and accurately tell us who is likely to not have colorectal cancer, and who should be referred for investigation.

“At a time when hospital services face a backlog as a result of Covid-19 measures, making this decision quickly can ensure the right people are investigated and treated as quickly as possible, which can help save lives.

“We know that FIT has accelerated interest in how FIT can be used in other patients, such as those with symptoms that have a higher risk of being colorectal cancer and we are now calling for FIT to be evaluated for use across the entire healthcare spectrum, not just in primary care, and in combination with other clinical markers of cancer such as blood test results.”

Each year, 1.8 million cases of colorectal cancer are diagnosed worldwide, and the disease causes 900,000 global deaths annually.

Dr Jodie Moffat, Cancer Research UK’s head of early diagnosis, said: “FIT is already being used for people who don’t have symptoms in the bowel screening programme.

“So it’s fascinating to see how this test may also be used in patients with low-risk symptoms to identify who needs further investigation.

“As with all tests, FIT isn’t perfect and some cases can be missed so it’s important that anyone whose symptoms persist, change or worsen contact their GP, even if they’ve recently had a negative FIT result.”