Quality of optical diagnosis of diminutive polyps and associated factors.

BACKGROUND AND AIMS: The aim of the study was to identify endoscopist-related and procedural factors that may be associated with the quality of optical diagnosis of diminutive polyps using narrow-band imaging (NBI). METHODS: All subjects who participated in a randomized trial on cap-assisted colonoscopy were eligible for the current study. Optical polyp diagnosis was an a priori outcome of the initial trial. Ten participating endoscopists used NBI to assess all of the diagnosed polyps as adenomatous or non-adenomatous in real-time and provided a degree of diagnostic certainty. The main outcome measures were quality benchmarks of optical diagnosis (negative predictive value [NPV] for diminutive rectosigmoid adenomas, agreement with pathology-based surveillance interval) and assessment of endoscopist-related and procedural factors potentially associated with the quality of optical diagnosis. RESULTS: A total of 1650 polyps were found in 607 patients, with 1311 polyps (79 %) being diminutive, of which 672 (53 %) were adenomatous. The NPV of optical diagnosis for rectosigmoid adenomas was 95 %. The optical diagnosis-based surveillance interval agreed with the pathology-based recommendation in 93 % of patients. Prior experience with image-enhanced endoscopy had no effect on optical diagnosis. Low and high adenoma detectors were not different in achieving the quality benchmarks. Cap-assisted colonoscopy was not associated with quality of optical diagnosis. Quality metrics of optical diagnosis remained similar during the first and second half of the study period. CONCLUSION: High quality optical diagnosis of diminutive polyps can be achieved and sustained by endoscopists previously inexperienced in this practice with minimal training. None of the examined factors appear to affect the quality of optical diagnosis; particularly, endoscopists' adenoma detection was not associated with optical diagnosis.

Cap-assisted colonoscopy and detection of Adenomatous Polyps (CAP) study: a randomized trial.

BACKGROUND AND STUDY AIM: Cap-assisted colonoscopy has improved adenoma detection in some but not other studies. Most previous studies have been limited by small sample sizes and few participating endoscopists. The aim of the current study was to evaluate whether cap-assisted colonoscopy improves adenoma detection in a two-center, multi-endoscopist, randomized trial. PATIENTS AND METHODS: Consecutive patients who presented for an elective colonoscopy were randomized to cap-assisted colonoscopy (4-mm cap) or standard colonoscopy performed by one of 10 experienced endoscopists. Primary outcome measures were mean number of adenomas per patient and adenoma detection rate (ADR). Secondary outcomes included procedural measures and endoscopist variation; a logistic regression model was employed to examine predictors of increased detection with cap use. RESULTS: A total of 1113 patients (64 % male, mean age 62 years) were randomized to cap-assisted (n = 561) or standard (n = 552) colonoscopy. The mean number of adenomas detected per patient in the cap-assisted and standard groups was similar (0.89 vs. 0.82; P = 0.432), as was the ADR (42 % vs. 40 %; P = 0.452). Cap-assisted colonoscopy achieved a faster cecal intubation time (4.9 vs. 5.8 minutes; P < 0.001), a similar cecal intubation rate (99 % vs. 98 %; P = 0.326), and a higher terminal ileum intubation rate (93 % vs. 89 %; P < 0.028). Cap-assisted colonoscopy resulted in a 20 % increase in ADR for some endoscopists and in a 15 % decrease for others. Individual preference for the cap was an independent predictor of increased adenoma detection in adjusted analysis (P < 0.001), whereas baseline low adenoma detection was not. CONCLUSION: Although the efficiency of cecal and terminal ileum intubation was slightly improved by cap-assisted colonoscopy, adenoma detection was not. Cap-assisted colonoscopy may be beneficial for selected endoscopists. TRIAL REGISTRATION: clinicalTrials.gov (NCT01935180).

Incomplete polyp resection during colonoscopy-results of the complete adenoma resection (CARE) study.

BACKGROUND & AIMS: Although the adenoma detection rate is used as a measure of colonoscopy quality, there are limited data on the quality of endoscopic resection of detected adenomas. We determined the rate of incompletely resected neoplastic polyps in clinical practice. METHODS: We performed a prospective study on 1427 patients who underwent colonoscopy at 2 medical centers and had at least 1 nonpedunculated polyp (5-20 mm). After polyp removal was considered complete macroscopically, biopsies were obtained from the resection margin. The main outcome was the percentage of incompletely resected neoplastic polyps (incomplete resection rate [IRR]) determined by the presence of neoplastic tissue in post-polypectomy biopsies. Associations between IRR and polyp size, morphology, histology, and endoscopist were assessed by regression analysis. RESULTS: Of 346 neoplastic polyps (269 patients; 84.0% men; mean age, 63.4 years) removed by 11 gastroenterologists, 10.1% were incompletely resected. IRR increased with polyp size and was significantly higher for large (10-20 mm) than small (5-9 mm) neoplastic polyps (17.3% vs 6.8%; relative risk = 2.1), and for sessile serrated adenomas/polyps than for conventional adenomas (31.0% vs 7.2%; relative risk = 3.7). The IRR for endoscopists with at least 20 polypectomies ranged from 6.5% to 22.7%; there was a 3.4-fold difference between the highest and lowest IRR after adjusting for size and sessile serrated histology. CONCLUSIONS: Neoplastic polyps are often incompletely resected, and the rate of incomplete resection varies broadly among endoscopists. Incomplete resection might contribute to the development of colon cancers after colonoscopy (interval cancers). Efforts are needed to ensure complete resection, especially of larger lesions. ClinicalTrials.gov Number: NCT01224444.