In the English NHS Bowel Cancer Screening Programme, men and women aged 60–74 years old are invited to participate in screening for bowel cancer every two years. At present, people are asked to complete a simple stool test (the guaiac Faecal Occult Blood test, gFOBt), which is sent to them in the post to be completed at home. People who have an abnormal test result (traces of blood are found in the stool) are invited for an examination of their large bowel to identify the source of the blood loss. Usually this examination is a colonoscopy, which is carried out by a specialist doctor or nurse in a hospital. One in every 5 people who have their colonoscopy, will have large (1cm across or larger) or multiple polyps found. It is known that people with large or multiple polyps are at higher risk of developing more polyps or bowel cancer in the future; for people with one large or 3–4 small polyps, this risk is classed as ‘intermediate’. Currently, it is recommended that everyone in the intermediate risk group is offered another colonoscopy after 3 years to look for polyps or early cancers – this is called a follow-up colonoscopy.
Although follow-up colonoscopy is the most effective way to protect people in the intermediate risk group from developing cancer, it is not perfect. Colonoscopy is uncomfortable, carries a small risk of complications, and is also demanding on health service resources. More effective, and more acceptable, alternatives to the 3-yearly follow-up colonoscopy are being sought.
The FIT for Follow-Up study is looking at whether offering a Faecal Immunochemical Test (FIT), once a year, to people in the intermediate risk group is an effective and safe alternative to 3-yearly follow-up colonoscopy. The study will also look at how acceptable the FIT is to this group of people as an alternative to follow-up colonoscopy, and whether it is a more effective use of health service resources. The FIT test is described below.