The Yield of Faecal Immunochemical Test in the Detection of Colorectal Cancer within a Fast-track Pathway at York, United Kingdom

Abstract

Aim: Access to colonoscopy was limited during the Coronavirus disease-2019 (COVID-19) pandemic peak. It was, therefore, of great importance that a tool such as faecal immunochemical test (FIT) be used to identify patients with a greater likelihood of colorectal cancer (CRC). Method: A prospective cohort of patients referred through the fast-track pathway was sent a FIT test. A cut-off of 7 µgHb/g was used as the threshold for a positive result. A receiver operating curve (ROC) was subsequently constructed to identify the ideal threshold for detecting cancer. Results: In total, there were 1,068 patients referred to the fast-track clinic. A greater proportion of patients who were FIT positive had CRC (17.4% vs. 0.4%, p=0.001) when compared with FIT negative patients. ROC curve analysis revealed an optimum sensitivity/specificity for detecting CRC using a FIT threshold of 19 µgHb/g. Conclusion: The yield for CRC is minimal in a FIT negative patient - such patients may be safely discharged, as long as a clinical safety net is in place. Using sensitivity and specificity analysis, patients with a FIT above 19 µgHb/g should be investigated urgently to exclude cancer.