The comparison of the efficiency of colon capsule endoscopy and optical colonoscopy in patients with positive immunochemical faecal occult blood test - multicentre, prospective study
Abstract
Background: Faecal immunochemical tests (FIT) have been used as an initial test in colorectal screening programmes. However, the majority of patients do not have advanced neoplasia on colonoscopy.
Colon capsule endoscopy (CCE) has the potential to reduce the need for optical colonoscopy (OC). Aim: The aim of the study was negative predictive value (NPV) of the second generation of colon capsule endoscopy (CCE2) for large polyps (>= 10 mm).
The secondary aims were: accuracy of detection of all polyps (polyps >= 6 mm and >= 10 mm) and cancers, number of complications and target population acceptance of both methods (CCE2 and OC). Material and methods: In this multicentre (3 gastroenterology units) feasibility study, 2nd generation of colon capsule endoscopy (CCE2) has been prospectively compared with OC in persons with positive semi-quantitative FIT with cut-off level 75 ng/ml.
Colonoscopy was performed within 10 hours after capsule ingestion. CCE2 videos were viewed independently by a nurse and a physician, both blinded to the results of OC.
Complications were assessed as serious (bleeding, perforation) or mild to moderate. The methods of acceptance were evaluated based on the questionnaire completed after both procedures (CCE2 and OC) were finished.
The interim analysis of results is presented. Results: From April 2016, 111 individuals have been enrolled, data from 54 persons have been analysed.
During optical colonoscopy, polyps were diagnosed in 37 persons (69%), polyps >= 6 mm and >= 10 mm in 22 (41%) and 12 (22%) persons, resp. The sensitivity of CCE2 for polyps >= 6 mm and >= 10 mm was 82% (95% confidence interval - CI 60-95%) and 75% (95% CI 43-95%), resp.
The specificity for polyps >= 6 mm and >= 10 mm reached 88% (95% CI 71-96%) and 93% (95% CI 81-99%), resp. There were 2 cancer diagnoses at both CCE2 and OC.
The negative predictive value of CCE2 for polyps >= 10 mm was 93% (95% CI 81-99%). Nurses identified 17 polyps >= 6 mm of 22 (77%) and 10 polyps >= 10 mm of 12 (83%) found on OC.
There was 1 stagnation of colon capsule in stenosing tumour of ascending colon recorded. No patient had any serious adverse event that was related to both methods.
A total of 40 patients (75%) preferred CCE2 as the primary screening method. Conclusion: Second generation of colon capsule has appeared to have a high negative predictive value for the detection of clinically relevant colorectal neoplasia in screening population.
This method might be considered as an adequate tool for colorectal cancer screening.