COLON CAPSULE ENDOSCOPY (CCE) IS AN EFFECTIVE FILTER TEST FOR COLONIC POLYP SURVEILLANCE

Aims Surveillance accounts for 30% of colonoscopy workload, the majority are normal. Identifying patients who require polypectomy would be advantageous. We aimed to assess CCE and/or faecal immunochemical test (FIT) as a potential filter in surveillance.

Methods Following ethical approval, patients due for polyp surveillance, aged 18-80 were identified from our waiting list, then invited by post for CCE and FIT. A CCE was considered positive if polyps or CRC was identified. CCE significant lesions (≥3 or >6mm polyps), incomplete studies and positive FITs (≥45 µg/g) were referred for endoscopy. CCE and endoscopy results were correlated. FIT accuracy was compared to CCE.

Results To date, 300 surveillance patients have been invited, the uptake rate was 46% (138/300). Of 114 analysed CCEs (mean age 65 (31-80), 62 (54%) males), 70% (80/114) were complete. Image quality was adequate in 103 (90%). Overall, CCE positivity was 70% (80/114) with 54% (43/80) having significant polyps. PPV of CCE was 94% (30/32 completed endoscopies). Significant extracolonic findings, requiring investigation, were reported in 1.8% (2/114). There were no complications.

The only characteristic associated with a positive CCE was older age ≥70 (OR 2.7, p=0.04, 95%CI 1.0547 to 6.9537).

2/98 (2%) returned FITs were positive, range 0-279 µg/g and mean of 9 µg/g. Positive FIT and CCE concordance was 100%, but FIT sensitivity was inadequate (3%) with an NPV of 30%. ROC analysis gave a sensitivity and specificity of 17% and 93%, respectively, for a FIT of ≥10 µg/g.

In all, 70/114 (61%) were referred for endoscopy, 18 (16%) sigmoidoscopy and 52 (46%) colonoscopy, 39 (34%) for an inadequate CCE. In our surveillance cohort, CCE reduced the need for any endoscopy by almost 40% (44/114) and 54% (62/114) were spared a colonoscopy.

Conclusions Unlike FIT, CCE is useful in selecting patients for polypectomy in polyp surveillance and avoiding unnecessary colonoscopy.