Evaluating the diagnostic accuracy of faecal immunochemical testing in the two-week wait referral pathway for colorectal cancer in the UK
Menée au Royaume-Uni à partir de données portant sur 1 841 patients ayant consulté en médecine générale pour des symptômes possiblement associés au cancer colorectal selon les critères NG12 du "National Institute for Health and Care Excellence", cette étude évalue la précision diagnostique du test FIT dans le cadre du parcours "2-week wait"
Objective: Colorectal cancer (CRC) is the second leading cause of cancer-related mortality in the UK. Early identification and timely intervention rely heavily on the faecal immunohistochemical test (FIT). However, FIT diagnostic accuracy varies, with a sensitivity ranging between 85% and 94% and a noteworthy negative predictive value (NPV) of 99%. The objective of this study was to evaluate the diagnostic accuracy of FIT in detecting CRC and advanced adenomas in patients referred through the 2-week wait (2WW) referral pathway following the National Institute for Health and Care Excellence (NICE) NG12 criteria.
Method: A retrospective analysis was conducted on 1841 patients who were referred through the 2WW pathway. Data on clinical characteristics, FIT test positivity (faecal haemoglobin
≥
10 µg/g), and subsequent investigations were obtained. The sensitivity, specificity, positive predictive value (PPV), and NPV were calculated based on the presence of adenomas (
≥
10 mm) or malignancies.
Results: Positive FIT results were observed in 73.4%, negative FIT in 25.9%, and 0.65% of patients lacked FIT availability. The sensitivity, specificity, PPV, and NPV for CRC detection compared to the presence of advanced adenoma or CRC were 96.49% vs. 93.6%, 26.56% vs. 30.2%, 7.31% vs. 21.8%, and 99.18% vs. 95.8%, respectively.
Conclusion: FIT showed the expected performance for CRC detection with an NPV of 99.18%, but a negative FIT result should not exclude investigation with colonoscopy due to a 4.2% likelihood of missing advanced adenomas. There is still a need for other types of testing for CRC screening.
Journal of Medical Screening , résumé, 2025