Retrospective Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. May 28, 2015; 21(20): 6261-6270
Published online May 28, 2015. doi: 10.3748/wjg.v21.i20.6261
Efficacy of cap-assisted colonoscopy according to lesion location and endoscopist training level
Dong Jun Kim, Hyung Wook Kim, Su Bum Park, Dae Hwan Kang, Cheol Woong Choi, Joung Boom Hong, Byoung Hoon Ji, Chang Seok Lee
Dong Jun Kim, Hyung Wook Kim, Su Bum Park, Dae Hwan Kang, Cheol Woong Choi, Joung Boom Hong, Department of Internal Medicine, Medical Research Institute, Pusan National University School of Medicine and Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan 626-770, Gyeongsangnam-do Province, South Korea
Byoung Hoon Ji, Department of Internal Medicine, Dong-eui Medical Center, Busan 614-851, South Korea
Chang Seok Lee, Department of Internal Medicine, Bongseng Memorial Hospital, Busan 601-723, South Korea
Author contributions: Kim DJ wrote the manuscript as the first author; Kim HW drafted and approved the final version of the manuscript; Park SB, Kang DH and Choi CW contributed to making critical revisions related to the important intellectual content of the manuscript; Hong JB, Ji BH and Lee CS contribute to the acquisition, analysis and interpretation of the data; all authors approved the final manuscript.
Supported by A 2-year research grant of Pusan National University.
Ethics approval: The study was reviewed and approved by the Institutional Review Board of PNUYH, IRB No. 05-2014-050.
Informed consent: All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
Conflict-of-interest: The authors declare no conflict of interest.
Data sharing: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Hyung Wook Kim, MD, PhD, Department of Internal Medicine, Pusan National University School of Medicine, Pusan National University Yangsan Hospital, Beomeo-ri, Mulgeum-eup, Yangsan 626-770, Gyeongsangnam-do Province, South Korea. mdkhwook@gmail.com
Telephone: +82-55-3601534 Fax: +82-55-3601536
Received: November 12, 2014
Peer-review started: November 14, 2014
First decision: December 26, 2014
Revised: January 27, 2015
Accepted: March 18, 2015
Article in press: March 19, 2015
Published online: May 28, 2015
Abstract

AIM: To evaluate the efficacy of cap-assisted colonoscopy (CAC) for detection of colorectal polyps and adenomas according to the lesion location and endoscopist training level.

METHODS: Patients 20 years or older, who underwent their first screening colonoscopy in a single tertiary center from May 2011 to December 2012 were enrolled in this study. All patients underwent either CAC or standard colonoscopy (SC), and all of the procedures were performed by 11 endoscopists (8 trainees and 3 experts). All procedures were performed with high-definition colonoscopes and narrow band imaging. The eight trainees had experiences of performing 150 to 500 colonoscopies, and the three experts had experiences of performing more than 3000 colonoscopies. A 4-mm-long transparent cap was attached to the end of a colonoscope in the CAC group. We retrospectively evaluated the number of polyps and adenomas, polyp detection rate (PDR), and the number of adenomas and adenoma detection rate (ADR) according to the lesion location and endoscopist training level between CAC and SC. We also evaluated the number of polyps and adenomas according to their size between CAC and SC.

RESULTS: Overall, PDR and ADR using CAC were significantly higher than those using SC for both whole colon (48.5% vs 40.7%, P = 0.012; 35.7% vs 28.3%, P = 0.012) and right-side colon (35.3% vs 26.6%, P = 0.002; 27.0% vs 16.9%, P < 0.001). The number of polyps and adenomas per patient using CAC was significantly higher than that using SC for both the whole colon (1.07 ± 1.59 vs 0.82 ± 1.31, P = 0.008; 0.72 ± 1.32 vs 0.50 ± 1.01, P = 0.003) and right-side colon (0.66 ± 1.18 vs 0.41 ± 0.83, P < 0.001; 0.46 ± 0.97 vs 0.25 ± 0.67, P < 0.001). In the trainee group, the PDR and ADR using CAC were significantly higher than those using SC for both the whole colon (46.7% vs 39.7%, P = 0.040; 33.9% vs 26.0%, P =0.012) and right-side colon (34.2% vs 26.5%, P = 0.015; 25.3% vs 15.9%, P = 0.001). In the expert group, the PDR and ADR using CAC were significantly higher than those using SC only for the right-side colon (42.1% vs 27.0%, P =0.035; 36.8% vs 21.0%, P = 0.020).

CONCLUSION: CAC is more effective than SC for detection of colorectal polyps and adenomas, especially when performed by trainees and when the lesions are located in the right-side colon.

Keywords: Colonoscopy, Cap-assisted colonoscopy, Colonic polyps, Adenoma, Colorectal neoplasm

Core tip: Missed lesions are the main cause of interval colon cancer. Cap-assisted colonoscopy (CAC) is one of the procedures which can reduce the incidence of missed lesion. Few studies have evaluated the efficacy of CAC based on location and size of lesions or training level of endoscopist. We evaluated the efficacy of CAC, according to the location and size of lesions and the training level of the endoscopists. We suggest that CAC can improve the detection of lesions for trainees in the whole colon and right-side colon, and even for experts in the right-side colon.