Randomized Controlled Trial
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Nov 15, 2020; 12(11): 1336-1345
Published online Nov 15, 2020. doi: 10.4251/wjgo.v12.i11.1336
Diagnostic value of novel retroflexion colonoscopy in the right colon: A randomized controlled trial
Wen-Kun Li, Yun Wang, Ya-Dan Wang, Kui-Liang Liu, Chun-Mei Guo, Hui Su, Hong Liu, Jing Wu
Wen-Kun Li, Ya-Dan Wang, Kui-Liang Liu, Chun-Mei Guo, Hui Su, Hong Liu, Jing Wu, Department of Gastroenterology, Beijing Shijitan Hospital, Capital Medical University, Beijing 100038, China
Wen-Kun Li, National Clinical Research Center for Digestive Diseases, Beijing 100050, China
Yun Wang, Ya-Dan Wang, Kui-Liang Liu, Chun-Mei Guo, Hui Su, Hong Liu, Department of Gastroenterology, Peking University Ninth School of Clinical Medicine, Beijing 100038, China
Jing Wu, Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University, National Clinical Research Center for Digestive Diseases, Beijing 100050, China
Author contributions: Wu J, Liu H, Liu KL, and Li WK completed the study concept and design; Li WK and Wang Y recruited the patients; Li WK and Wang Y acquired the data; Li WK performed statistical analysis and drafted the manuscript; Liu KL, Wang YD, Guo CM, and Su H performed colonoscopy; Wu J and Liu KL provided critical review of the manuscript; all authors read and approved the final manuscript.
Supported by Digestive Medical Coordinated Development Center of Beijing Hospitals Authority, No. XXZ015; Capital Citizens Health Cultivation Project of Beijing Municipal Science & Technology Commission, No. Z161100000116084; Medical and Health Public Foundation of Beijing, No. YWJKJJHKYJJ-B17262-067; and Science and Technology Development Project of China State Railway Group, No. N2019Z004.
Institutional review board statement: The study was reviewed and approved by the Institutional Review Board of Beijing Shijitan Hospital, Capital Medical University (Approval No. 2018-59).
Clinical trial registration statement: This study is registered at http://www.chictr.org.cn/. The registration identification number is ChiCTR2000031186.
Informed consent statement: All study participants provided informed written consent prior to study enrollment.
Conflict-of-interest statement: The authors declare that there is no conflict of interests in this study.
Data sharing statement: Dataset available from the corresponding author at bjsjtyywj@ccmu.edu.cn.
CONSORT 2010 statement: The authors have read the CONSORT 2010 Statement, and the manuscript was prepared and revised according to the CONSORT 2010 Statement.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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/
Corresponding author: Jing Wu, PhD, Director, Professor, Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University, National Clinical Research Center for Digestive Diseases, No. 95 Yongan Road, Xicheng District, Beijing 100050, China. bjsjtyywj@ccmu.edu.cn
Received: July 13, 2020
Peer-review started: July 13, 2020
First decision: September 17, 2020
Revised: September 27, 2020
Accepted: October 15, 2020
Article in press: October 15, 2020
Published online: November 15, 2020
Processing time: 122 Days and 3.1 Hours
Abstract
BACKGROUND

Colonoscopy is the accepted gold standard for the detection of colorectal cancer. However, colonoscopy is less effective in preventing colon cancer in the right side compared with the left side.

AIM

To investigate the feasibility of a novel type of retroflexion colonoscope, EC-3490Ti colonoscope, for detection of proximal colon lesions.

METHODS

In this prospective trial, we recruited patients who underwent colonoscopy for screening or surveillance. When the endoscopists could not grasp the whole observation of the right-side colon mucosa in the forward view (FV), insertion and withdrawal were repeatedly performed in the FV group with the EC38-i10F colonoscope while retroflexion was performed in the retroflexed view (RV) group with the EC-3490Ti colonoscope. Adenoma detection rate, the total number of adenomas per positive participant, the success rate of retroflexion, and endoscope withdrawal time were recorded and compared.

RESULTS

The total adenoma detection rate (39.3% vs 37.7%, P = 0.646) did not show any significant difference between the two groups. However, the polyp detection rate (59.6% vs 51.0%, P = 0.002), adenoma detection rate in the right colon (21.6% vs 14.4%, P = 0.012), and the total number of adenomas per positive participant (2.1 vs 1.7, P = 0.011) reached statistical significance. Retroflexion was achieved in 91.7% of our cohort. Compared with the FV group, the withdrawal time was significantly prolonged in the RV group (586.1 ± 124.4 s vs 508.8 ± 129.6 s, P < 0.001). In contrast, the proportion of additional ancillary pressure decreased (27.4% vs 45.7%, P < 0.001), and the visual analog scale pain scores did not increase (2.7 ± 1.4 vs 2.8 ± 1.4, P = 0.377).

CONCLUSION

Retroflexion in the proximal colon could be performed successfully and safely with the EC-3490Ti colonoscope. This maneuver could detect more adenomas effectively.

Keywords: Colorectal adenoma; Retroflexion; Right colon; Adenoma detection rate; Cancer

Core Tip: The current prospective randomized trial assessed the feasibility and efficacy of retroflexion colonoscopy in the proximal colon. Unlike previous studies, retroflexion was performed when the mucosa could not be exposed completely in the forward view due to the folds and flexures, instead of second insertion and withdrawal. Retroflexion in the right colon could be performed successfully and safely with the EC-3490Ti colonoscope and detect more adenomas effectively.