ClinicalTrials.gg
CompletedNCT04124393Updated Dec 8, 2023

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

An interventional study of Colon Polypectomy in Right Colon Adenoma Miss Rate and Right Colon Hyperplastic Polyp Miss Rate, sponsored by Evergreen General Hospital, Taiwan. Completed at 1 site in Taiwan. Open to participants aged 45 Years to 80 Years. Per ClinicalTrials.gov, last updated 2023-12-08.

Sponsored by Evergreen General Hospital, Taiwan · Not applicable, Interventional, and Treatment

Phase
Not applicable
Study type
Interventional
Enrollment
386
Allocation
Randomized
Ages
45 Years to 80 Years
Sex
All
01

Study summary

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.

Read the 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.

02

Conditions studied

  • Right Colon Adenoma Miss Rate
  • Right Colon Hyperplastic Polyp Miss Rate

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03

In context

Polyps

312 studies on the registry are indexed under Polyps; 60 are open to participants now.

This study's enrollment of 386 is above the median of 150 across 204 interventional studies indexed under Polyps.

Browse Polyps studies →

Lead sponsor

Evergreen General Hospital, Taiwan is the lead sponsor of 11 studies on the registry; 2 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
45 Years to 80 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

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

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 .
Terms in these criteria, in plain language(1)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Single (Outcomes assessor)
Enrollment
386 participants (actual)

Study arms

  • 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

  • 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

Interventions

  • ProcedureColon 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.

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What researchers measure

Primary outcomes

  1. 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.

    Time frame: One day

  2. 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.

    Time frame: One day

07

Study locations

1 site
  • Evergreen General Hospital
    Taoyuan, Taiwan
08

References and documents

Publications

  • 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. PubMed 23744612 ↗
  • 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. PubMed 29981753 ↗
  • 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. PubMed 29505552 ↗
  • 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. PubMed 31412789 ↗
  • 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. PubMed 30738046 ↗

Individual participant data

Plan to share: No

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Ran from Dec 2019 to primary completion in Nov 2022, 35 months.

Of 68 non-industry interventional studies with no phase under Polyps, half reached primary completion within 23 months of starting (the median), counting those still running; a quarter within 12 and three quarters within 42. This study's 35 months is above that.

Counting every sponsor, half of 79 studies reached it within 23 months; a quarter within 12 and three quarters within 42.

How these figures are worked out, and which studies are left out of them.

Registered
Oct 10, 2019
First posted
Oct 11, 2019
StartActual
Dec 1, 2019
Primary completionActual
Nov 30, 2022
CompletionActual
Dec 31, 2022
Last update
Dec 8, 2023
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Dec 8, 2023, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT04124393
Lead 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
Responsible party
Sponsor
First posted
Oct 11, 2019
Start date
Dec 1, 2019
Primary completion
Nov 30, 2022
Completion
Dec 31, 2022
Last update
Dec 8, 2023

Study contacts

Chiliang Cheng, M.D.
principal investigator · Evergreen General Hospital

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Dec 2023. You cannot join it, but the record below documents what was studied.

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