Multicenter Evaluation of Right Colon Polyp Miss Rates Using Water Exchange Versus CO2 Insufflation

Comparing Right Colon Adenoma and Hyperplastic Polyp Miss Rates in Colonoscopy Using Water Exchange and CO2 Insufflation: A Multicenter Randomized Tandem Study

A prospective multicenter randomized controlled trial (RCT) comparing water exchange (WE) colonoscopy and carbon dioxide (CO2) insufflation in terms of right colon combined adenoma miss rate (AMR) and hyperplastic polyp miss rate (HPMR) by tandem inspection.

Study Overview

• Status: Completed
• Conditions: Right Colon Adenoma Miss Rate; Right Colon Hyperplastic Polyp Miss Rate
• Intervention / Treatment: Procedure: Colon Polypectomy

Detailed Description

This will be a prospective RCT comparing CO2 insufflation and WE in terms of right colon combined AMR and HPMR by tandem inspection. It will be a multicenter study conducted in three community hospitals (Evergreen General Hospital, Taoyuan; Dalin Tzu-Chi Hospital, Chiayi; Taipei Medical University Hospital, Taipei) in Taiwan. Consecutive patients aged 45 years or older undergoing colonoscopy for screening, surveillance, and positive FIT will be considered for enrollment from December 2019 to May 2021. A written informed consent will be obtained from all participating patients. Participants will be randomized in a 1:1 ratio to undergo either the CO2 insufflation colonoscopy (CO2 group) or WE colonoscopy (WE group). WE colonoscopies will be performed by five board-certified colonoscopists (Chi-Liang Cheng, Yen-Lin Kuo [Evergreen General Hospital]; Yu-Hsi Hsieh, Chih-Wei Tseng [Dalin Tzu-Chi Hospital]; Jui-Hsiang Tang [Taipei Medical University Hospital]. Standard colonoscopes (CF-Q260AL/I, CF-HQ290L/I; Olympus Medical Systems Corp., Tokyo, Japan) will be used. Felix W. Leung will be involved in the study design, data analyses, and report preparation, but not in patient enrollment. Antispasmodic medication will not be administered during colonoscopy examination. CO2 insufflation will be used for CO2 group and the withdrawal phase of the WE group. In the WE group, the air pump will be turned off before starting the procedure. During the insertion phase, air and residual water or feces in the rectum will be aspirated, and then the colon will be irrigated with warm water. When the cecum is reached and after most of the water is suctioned to collapse the cecal lumen, CO2 will be opened. In the CO2 group, colonoscopy is performed in the usual fashion, with minimal insufflation required to aid insertion. Cleaning in the CO2 group will be performed entirely during withdrawal. Upon arriving at the cecum, CO2 insufflation will be used in both groups and the scope will be withdrawn from the cecum to the hepatic flexure, with inspection of the mucosa at the same time. All polyps identified will be resected and sent for pathology evaluation. The most distal part of the hepatic flexure will be marked by a forceps biopsy and then the scope will be reinserted into the cecum by the first endoscopist using CO2 insufflation. A tandem inspection of the right colon will then be performed by a blinded endoscopist in both study groups. All polyps found herein will be counted as the missed polyps. After the second withdrawal to the mark of distal hepatic flexure, the remainder of the colon will be examined in a standard manner by the first endoscopist. Polyp search and resection will be performed during the withdrawal phase in both groups. Insertion polypectomy will not be performed.

• Study Type: Interventional
• Enrollment (Actual): 386
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Chiliang Cheng, M.D.; Phone Number: 1510 +886-3-4631230; Email: chiliang.cheng@gmail.com
• Study Contact Backup: Name: Chiliang Cheng, M.D.; Phone Number: +886-919768058; Email: chiliang.cheng@gmail.com

Study Locations

• Taiwan
  • Taoyuan, Taiwan
    • Evergreen General Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 45 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Consecutive patients aged 45 years or older undergoing colonoscopy for screening, surveillance, and positive fecal immunochemical test will be considered for enrollment.

Exclusion Criteria:

• Familial adenomatous polyposis and hereditary non-polyposis colorectal cancer (CRC) syndrome, personal history of CRC or inflammatory bowel disease, previous colonic resection, obstructive lesions of the colon, gastrointestinal bleeding, allergy to fentanyl, midazolam or propofol, American Society of Anesthesiology classification of physical status grade 3 or higher, mental retardation, pregnancy, and refusal to provide a written informed consent.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Water Exchange (WE) Colonoscopy; In the WE group, the air pump will be turned off before starting the procedure. During the insertion phase, the colon will be irrigated with warm water (32C-35C). WE entails the infusion of water to open the lumen and simultaneous suction if the endoscope has two channels, and sequentially if the endoscope has only one channel. When the cecum is reached and after most of the water is suctioned to collapse the cecal lumen, CO2 will be opened. The colonoscope will be withdrawn to the hepatic flexure. All polyps identified will be resected (colon polypectomy). The colonoscope will then be reinserted into the cecum by the first endoscopist. A tandem inspection of the right colon will be performed by a blinded endoscopist. All polyps found herein will be counted as the missed polyps. After the second withdrawal to the distal hepatic flexure, the remainder of the colon will be examined in a standard manner by the first endoscopist.	Procedure: Colon Polypectomy; Polyp search and resection will be performed entirely during the withdrawal phase in both WE and CO2 groups. Insertion inspection and polypectomy will not be performed. All polyps in the proximal colon, defined as cecum, ascending colon, hepatic flexure, and transverse colon, will be removed irrespective of their size and appearance.
Active Comparator: CO2 Insufflation Colonoscopy; In the CO2 group, colonoscopy is performed in the usual fashion, with minimal insufflation required to aid insertion. Cleaning in the CO2 group will be performed entirely during withdrawal. Upon arriving at the cecum, CO2 insufflation will be used and the colonoscope will be withdrawn from the cecum to the hepatic flexure. All polyps identified will be resected (colon polypectomy). Then, the colonoscope will be reinserted into the cecum by the first endoscopist. A tandem inspection of the right colon will be performed by a blinded endoscopist. All polyps found herein will be counted as the missed polyps. After the second withdrawal to the distal hepatic flexure, the remainder of the colon will be examined in a standard manner by the first endoscopist.	Procedure: Colon Polypectomy; Polyp search and resection will be performed entirely during the withdrawal phase in both WE and CO2 groups. Insertion inspection and polypectomy will not be performed. All polyps in the proximal colon, defined as cecum, ascending colon, hepatic flexure, and transverse colon, will be removed irrespective of their size and appearance.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Right Colon Adenoma Miss Rate	Lesions detected on the tandem right colon examination will be used for the calculation of adenoma miss rate. Right colon adenooma miss rate will be calculated as the the number of adenomas missed during the first right colon examination divided by the total number of adenomas detected during both the first and tandem right colon examinations.	One day
Right Colon Hyperplastic Polyp Miss Rate	Lesions detected on the tandem right colon examination will be used for the calculation of hyperplastic polyp miss rate. Right colon hyperplastic polyp miss rate will be calculated as the the number of hyperplastic polyps missed during the first right colon examination divided by the total number of hyperplalstic polyps detected during both the first and tandem right colon examinations.	One day

Collaborators and Investigators

• Sponsor: Evergreen General Hospital, Taiwan
• Collaborators: Taipei Medical University Hospital; Dalin Tzu Chi General Hospital; Sepulveda Ambulatory Care Center, VA Greater Los Angeles Healthcare System
• Investigators: Principal Investigator: Chiliang Cheng, M.D., Evergreen General Hospital

Publications and helpful links

General Publications

• Zhao S, Wang S, Pan P, Xia T, Chang X, Yang X, Guo L, Meng Q, Yang F, Qian W, Xu Z, Wang Y, Wang Z, Gu L, Wang R, Jia F, Yao J, Li Z, Bai Y. Magnitude, Risk Factors, and Factors Associated With Adenoma Miss Rate of Tandem Colonoscopy: A Systematic Review and Meta-analysis. Gastroenterology. 2019 May;156(6):1661-1674.e11. doi: 10.1053/j.gastro.2019.01.260. Epub 2019 Feb 6.
• le Clercq CM, Bouwens MW, Rondagh EJ, Bakker CM, Keulen ET, de Ridder RJ, Winkens B, Masclee AA, Sanduleanu S. Postcolonoscopy colorectal cancers are preventable: a population-based study. Gut. 2014 Jun;63(6):957-63. doi: 10.1136/gutjnl-2013-304880. Epub 2013 Jun 6.
• Fuccio L, Frazzoni L, Hassan C, La Marca M, Paci V, Smania V, De Bortoli N, Bazzoli F, Repici A, Rex D, Cadoni S. Water exchange colonoscopy increases adenoma detection rate: a systematic review with network meta-analysis of randomized controlled studies. Gastrointest Endosc. 2018 Oct;88(4):589-597.e11. doi: 10.1016/j.gie.2018.06.028. Epub 2018 Jul 5.
• Leung FW, Koo M, Cadoni S, Falt P, Hsieh YH, Amato A, Erriu M, Fojtik P, Gallittu P, Hu CT, Leung JW, Liggi M, Paggi S, Radaelli F, Rondonotti E, Smajstrla V, Tseng CW, Urban O. Water Exchange Produces Significantly Higher Adenoma Detection Rate Than Water Immersion: Pooled Data From 2 Multisite Randomized Controlled Trials. J Clin Gastroenterol. 2019 Mar;53(3):204-209. doi: 10.1097/MCG.0000000000001012.
• Cheng CL, Kuo YL, Hsieh YH, Tang JH, Leung FW. Water exchange colonoscopy decreased adenoma miss rates compared with literature data and local data with CO2 insufflation: an observational study. BMC Gastroenterol. 2019 Aug 14;19(1):143. doi: 10.1186/s12876-019-1065-2.

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2019
• Primary Completion (Actual): November 30, 2022
• Study Completion (Actual): December 31, 2022

Study Registration Dates

• First Submitted: October 10, 2019
• First Submitted That Met QC Criteria: October 10, 2019
• First Posted (Actual): October 11, 2019

Study Record Updates

• Last Update Posted (Estimated): December 8, 2023
• Last Update Submitted That Met QC Criteria: December 3, 2023
• Last Verified: December 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Neoplasms by Histologic Type; Neoplasms; Neoplasms, Glandular and Epithelial; Pathological Conditions, Anatomical; Adenoma; Hyperplasia; Polyps
• Other Study ID Numbers: EGH-2020

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No