Effect of Water Exchange Method on Adenoma Miss Rates in Patients Undergoing Selective Polypectomy

Effect of Water Exchange Method on Adenoma Miss Rates in Patients Undergoing Selective Polypectomy: a Single-centered, Randomized Controlled Study

Patients with colorectal adenomas are suggested to receive polypectomy. A substantial number of adenomas may be missed in patients with polyps found by previous colonoscopy. And water exchange (WE) method may increase the detection of missed adenoma compared with traditional air insufflation (AI) colonoscopy. The investigators aim to investigate whether water exchange colonoscopy method, compared with air insufflation method, can improve the detection of missed adenomas in patients undergoing selective polypectomy.

Study Overview

• Status: Unknown
• Conditions: Adenoma
• Intervention / Treatment: Other: Water exchange (WE) method; Other: Air insufflation (AI) method.

Detailed Description

For WE method, the air pump was turned off for the full duration of insertion to avoid inadvertent air insufflations and colon elongation. Residual air in the lumen was suctioned to minimize angulations at flexures. Water at 37°C was infused with a pump (Olympus) through the biopsy channel to confirm correct tip orientation for scope advancement. The infused water was removed predominantly by suction when the colonoscope was smoothly advanced during the insertion phase, and turbid luminal water due to residual feces was exchanged by clean water until the lumen was clearly visualized. Occasionally, if it was difficult to determine whether the colonoscope tip was in the cecum, air was allowed to be insufflated for observation. If the position of the scope tip was confirmed to be not in the cecum, insufflated air would be removed by suction and the WE method would be continuously used until successful intubation.

For the AI method, water was not used, and air was insufflated during insertion.

Air was insufflated to distend the lumen for inspection and biopsy or polypectomy during withdrawal for both methods. Polyps will be removed by forceps biopsy (polyps size <3mm), cold snare technique (3-6mm) or endoscopic mucosal resection (size≥6mm).

• Study Type: Interventional
• Enrollment (Anticipated): 450
• Phase: Not Applicable

Contacts and Locations

Study Locations

• China
  • Shaanxi
    • Xi'an, Shaanxi, China, 710032
      • Recruiting
      • Endoscopic center, Xijing Hospital of Digestive Diseases
      • Contact: Gui Ren, MD; Phone Number: +862984771536; Email: renguigz@hotmail.com
      • Principal Investigator: Gui Ren, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age 18-80 patients undergoing selective polypectomy

Exclusion Criteria:

• Polyps found more than 6 months
• Patients with polyposis syndrome or hereditary nonpolyposis colorectal cancer
• Patients with history of inflammatory bowel disease
• Patients with planning to undergo Endoscopic Submucosal Dissection(ESD)
• Patients not undergoing standard bowel preparation
• Patients with solid feces in the last stool after bowel preparation
• Patients considered to be high risk for bleeding during Endoscopic mucosal resection (EMR), e.g. using antiplatelet drugs (clopidogrel) within 5 days before the current colonoscopy
• Hemodynamically unstable
• Pregnant women
• Unable to provide 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
Experimental: Water exchange (WE) method; Water exchange (WE) method was used for insertion to the cecum.	Other: Water exchange (WE) method; Water exchange (WE) method was used for insertion to the cecum. And air was insufflated to distend the lumen for inspection and biopsy or polypectomy during withdrawal procedure.
Active Comparator: Air insufflation (AI) method; Air insufflation (AI) method was used for insertion to the cecum.	Other: Air insufflation (AI) method.; Air insufflation (AI) method was used for insertion to the cecum. And air was insufflated to distend the lumen for inspection and biopsy or polypectomy during withdrawal procedure.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adenoma miss rate	Adenoma miss rate was calculated as the number of patients with one and more additional adenomas during polypectomy procedure divided by the total number of patients in each group.	12 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
adenoma-level miss rate	Adenoma-level miss rate was calculated as the number of additional adenomas detected in polypectomy procedure divided by the total number of adenomas in each group.	12 months
Advanced adenoma miss rate/Miss advanced adenoma per colonoscopy	Advanced adenoma: any with 3 or more adenomas of any size, 1 or more large adenomas 1 cm, or 1 or more adenomas with villous architecture or highgrade dysplasia.	12 months
Adenoma per positive patient (APP)	The mean number of adenoma per positive patient	12 months
Quality of Bowel Preparation	The Boston Bowel Preparation Scale (BBPS): cleanliness of each part of the colon: 0=unprepared colon segment with mucosa not seen because of solid stool that cannot be cleared; 1=portion of mucosa of the colon segment seen, but other areas of the colon segment not well seen because of staining, residual stool, and/or opaque liquid; 2=minor amount of residual staining, small fragments of stool and/or opaque liquid, but mucosa of colon segment seen well; 3=entire mucosa of colon segment seen well with no residual staining, small fragments of stool, or opaque liquid.	12 months
Complication rate	Bleeding, perforation and others	12 months
Pain Scores on the Visual Analog Scale compared with previous colonoscopy	0 = no pain, to 10 = most severe pain	12 months

Collaborators and Investigators

• Sponsor: Air Force Military Medical University, China

Publications and helpful links

General Publications

• Hewett DG, Rex DK. Cap-fitted colonoscopy: a randomized, tandem colonoscopy study of adenoma miss rates. Gastrointest Endosc. 2010 Oct;72(4):775-81. doi: 10.1016/j.gie.2010.04.030. Epub 2010 Jun 25.
• Veitch AM, Vanbiervliet G, Gershlick AH, Boustiere C, Baglin TP, Smith LA, Radaelli F, Knight E, Gralnek IM, Hassan C, Dumonceau JM. Endoscopy in patients on antiplatelet or anticoagulant therapy, including direct oral anticoagulants: British Society of Gastroenterology (BSG) and European Society of Gastrointestinal Endoscopy (ESGE) guidelines. Gut. 2016 Mar;65(3):374-89. doi: 10.1136/gutjnl-2015-311110.
• Ren G, Wang X, Luo H, Yao S, Liang S, Zhang L, Dong T, Chen L, Tao Q, Guo X, Han Y, Pan Y. Effect of water exchange method on adenoma miss rate of patients undergoing selective polypectomy: A randomized controlled trial. Dig Liver Dis. 2021 May;53(5):625-630. doi: 10.1016/j.dld.2020.11.012. Epub 2020 Dec 31.

Study record dates

Study Major Dates

• Study Start: August 1, 2016
• Primary Completion (Anticipated): August 1, 2017
• Study Completion (Anticipated): August 1, 2017

Study Registration Dates

• First Submitted: August 19, 2016
• First Submitted That Met QC Criteria: August 25, 2016
• First Posted (Estimate): August 26, 2016

Study Record Updates

• Last Update Posted (Estimate): August 26, 2016
• Last Update Submitted That Met QC Criteria: August 25, 2016
• Last Verified: August 1, 2016

More Information

Terms related to this study

• Keywords: Polyps; Water exchange colonoscopy; Adenoma miss rate
• Additional Relevant MeSH Terms: Neoplasms by Histologic Type; Neoplasms; Neoplasms, Glandular and Epithelial; Adenoma
• Other Study ID Numbers: KY20162059-2

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED