IDDF2024-ABS-0055 Can double faecal immunochemical tests be used as alternatives to post-polypectomy surveillance colonoscopy?

Background Colonoscopy is performed for post-polypectomy surveillance, but shorter intervals of follow-up colonoscopy are not cost-effective for low-risk post-polypectomy populations. Faecal immunochemical testing (FIT) may be a viable alternative for such patients. This study aimed to evaluate the use of two FIT kits in detecting outcomes compared to surveillance colonoscopy and to understand post-polypectomy surveillance patients’ preferences and barriers to colonoscopy. Methods Patients scheduled for post-polypectomy surveillance colonoscopy were provided two FIT kits to complete prior to bowel preparation. Patients self-reported preferences and perceived barriers post-colonoscopy. FIT kit and colonoscopy outcomes were collected. Results Polyp prevalence was 48.1% in our sample of 106 patients. Double FIT showed sequential sensitivity and specificity of 24.0% and 88.9%, yielding a positive predictive value (PPV) of 66.6%, negative predictive value (NPV) of 55.9%, and accuracy of 57.7%. Most patients with adenomatous polyps had polyp(s) sized <5mm (N=34; 68.0%). Only 3 (6.0%) had polyp(s) larger than 9mm. Most patients were acceptive of annual FIT (68.0%) or 3–5-year intervals (24.0%). Only 25 patients (24.0%) preferred colonoscopy. Conclusions Double FIT appears preferable over surveillance colonoscopy. Nonetheless, the test performance of double FIT appears inadequate for general use in the detection of adenomatous polyps at this juncture. Future studies should examine the test performance of double FIT more rigorously in triaging post-polypectomy patients who might have more specific or serious pathologies.