FIT for purpose: enhanced applications for faecal immunochemical tests

Colorectal cancer (CRC) is one of the most prevalent cancers. Early diagnosis has a major impact on survival, and can be achieved with screening programs. CRC screening participation with faecal immunochemical tests (FIT) detects CRC at an earlier and more treatable stage, resulting in a decrease in mortality, and a reduction in incidence through detection and subsequent removal of precursor adenomas. CRC screening, as well as the need for individuals to have ongoing surveillance colonoscopy following diagnosis of neoplasia, results in an increasing burden on colonoscopy resources. This can result in lengthy waiting times for colonoscopy, with a potential consequence being increased stage of disease as well as patient anxiety. These issues associated with FIT programs could be addressed through improving test accuracy in both sensitivity and specificity, as well as tailoring screening to the risk factors of the individual. FIT hemoglobin (Hb) concentrations in combination with clinical risk factors could be used to plan screening intervals as well as triage for diagnostic colonoscopy. Smart use for FIT could also be within symptomatic patients or in the higher risk population with a view to achieving more efficient and cost-effective use of colonoscopy. The evidences underlying these strategies are explored in this review, with a focus on enhanced applications of FIT to reduce the burden on limited colonoscopy resources.