Almost 40 per cent of people who have abnormal results from bowel cancer screening tests and are referred for further investigation ignore their next screening invitation two years later, according to a Cancer Research UK study* published in the British Journal of Cancer.
In contrast, just 13 per cent of those who had a normal result did not continue with screening. People who receive an abnormal result from the test - called the Faecal Occult Blood test (FOBt)** - are referred for follow up tests including a colonoscopy to rule out a cancer diagnosis but could be at risk if they fail to continue with bowel cancer screening.
The team, from the Health Behaviour Research Centre at University College London (UCL), previously found*** that 11 - 12 per cent of those referred for further investigations do not attend the appointments for this.
The Cancer Research UK team looked at almost 40,000 people's behaviour to find out if their experience of bowel cancer screening affected the likelihood of doing the same test two years later.
Lead author, Dr Siu Hing Lo from the Health Behaviour Research Centre at UCL, said: "Our research has identified a small but high risk group who are failing to continue with bowel cancer screening tests. We urgently need to understand why people are dropping out of bowel cancer screening and not attending the follow up investigations as we know the test saves lives."
The NHS Bowel Screening Programme aims to detect bowel cancer at an early stage - before people have obvious symptoms and when treatment is much more likely to be successful. The test picks up blood in stool samples which can be a symptom of bowel cancer. When blood is detected people are invited for a colonoscopy and if cancer is diagnosed treatment can begin as soon as possible to maximise the chances of survival.
Men and women aged 60 - 74 in England, Wales and Northern Ireland, and 50 - 74 in Scotland, are sent an invitation letter and then a home screening kit every two years****.
Father-of-two John Marsh, 67, from London was diagnosed with bowel cancer in 2007. He said: "It was thanks to the bowel cancer screening programme that my cancer was found at an early stage. I'd had no symptoms at all but a month after my 60th birthday, I got a screening test in the post. I'd never heard of it, but I did it straightaway. I didn't have a second thought about doing it.
"After doing the test I got a letter asking me to do the test again and then I was called for a colonoscopy. I saw the consultant and he confirmed it was bowel cancer. I had surgery in the March but I didn't need chemotherapy. I've had three colonoscopies since then and they've all been clear.
"I know a few people who haven't done it and I just can't understand it."
Bowel cancer accounts for 13 per cent of cancers diagnosed in the UK, with more than 41,000 people diagnosed with bowel cancer each year. It kills over 16,000 people each year.
Julie Sharp, head of health information at Cancer Research UK, said: "Bowel cancer is the fourth most common cancer and screening is important to help us beat the disease. Only 58 per cent of people who are offered bowel screening in England complete their testing kits, and it's a concern to see that people who have abnormal results are dropping out of the screening programme.
"It's really important to repeat the test every two years and Cancer Research UK is working hard to make people aware of bowel screening and help to remove any barriers that might be stopping them from taking the test."