8 Focus on FIT FIT Negative Follow-Up Safety-netting patients with a low faecal haemoglobin concentration and modifying the current patient pathway to improve patient care. Dr. James Turvill, Consultant Gastroenterologist, York Teaching Hospital NHS Foundation Trust Dr. James Turvill is a screening endoscopist within the Bowel Cancer Screening Programme and has an interest in inflammatory bowel disease and gastrointestinal cancer. Since 2008 he has developed a research interest in the use of biomarkers to facilitate the diagnosis and monitoring of gastrointestinal disease. Currently he is working with Y&H AHSN in the implementation of a faecal calprotectin (fCAL) care pathway to support NICE DG11 and with the Y&H Cancer Alliance in the introduction of faecal immunochemical testing (FIT) in patients with suspected colorectal cancer. Here Dr. Turvill summarises his presentation made at the Digestive Diseases Day, where he discussed his study at York Hospital and the importance of negative FIT follow-up for patients. BACKGROUND “NICE guidance is about finding people with cancer so that we can make a difference. FIT should be seen as a technology designed to facilitate this process. So I am a little unsettled about the concept of using FIT as a test to ‘rule-out’ colorectal cancer (CRC), though this is what it is good at. Instead we need to use it to ‘rule-in’ patients and so find CRC early. And here lies the challenge. INTRODUCTION In thinking about FIT negative follow up we need to understand what is currently happening in primary and secondary care and then, what a FIT positive result will mean for the future. Then for the FIT negative patient we need to consider consequentialism over essentialism. If you look at a cohort of patients referred from primary care fulfilling NICE NG12, that is at high risk of CRC, around two-thirds of patients will have ‘functional disorders’ (predominantly the irritable bowel syndrome (IBS), but also benign anal canal bleeding and iron deficient anaemia of unknown cause). Currently it is this group of patients that secondary care clinicians are focussing on since these are judged to increase healthcare costs by the time constrained consumption of resource in achieving a diagnosis. Then 4% of patients will have CRC and a further 4% will have significant polyps (those 10mm or larger). Then there will be a complex, nonmalignant group of patients, making up 12%, generally termed ‘organic enteric disease’ that will need secondary care intervention. This includes patients with IBD, microscopic colitis and diverticulitis. There will be another similarly sized group with diminutive polyps (<1 cm). Lastly, around 4% of the cohort will have non-enteric disease and within this group there will be other cancers, which FIT will not identify. This means that around 40% of all the cancers in patients referred through NICE NG12 with suspected CRC will be non-CRC. Therefore, the success of using FIT will not depend on how well it identifies CRC but on how well it helps us identify the 40% of cancer patients without CRC that are currently being referred through NG12. So how does FIT allow us to untangle this disparate group? We have looked prospectively at 700 patients referred from primary care under NG12 with suspected CRC. Each patient provided two stool samples prior to investigation allowing us to perform two FIT and two fCAL tests. We had hypothesized that a repeat test might improve the specificity-sensitivity profile of the assays and so enhance diagnostic accuracy. We tested FIT using the Kyowa Medex HMJACKarc and calprotectin using BÜHLMANN fCAL® ELISA (both supplied by Alpha Laboratories Ltd). If we extrapolate our data to a population of 1000 patients and apply ‘detectable’ haemoglobin as the FIT cut-off value you get 290 positive, and 710 negative results. You will pick up almost all, but importantly not all, CRC (I am reconciled to the fact that regardless of what the cut-off is, some, but very little CRC will be missed).
RkJQdWJsaXNoZXIy MTUyODc1Mw==