CClinicalTrials.gg
CompletedNCT02889679Updated Dec 20, 2018

Underwater Resection of Non-pedunculated Colorectal Lesions

An interventional study of Underwater resection and Conventional (gas distended colon) resection in Colorectal Neoplasms, sponsored by VA Northern California Health Care System. Completed at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2018-12-20.

Sponsored by VA Northern California Health Care System · Not applicable, Interventional, and Treatment

Phase
Not applicable
Study type
Interventional
Enrollment
600
Allocation
Randomized
Ages
18 Years and older
Sex
All
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Study summary

The aim of this study is to compare the efficacy of underwater resection (polypectomy) versus conventional polypectomy techniques for small and large colorectal lesions identified during colonoscopy.

Read the detailed description

Conventional endoscopic resection of small and large (≥1cm) colorectal lesions is well established and performed with the colon fully distended with gas. Conventional polypectomy is effective, but the rate of incomplete resection is approximately 10%. Incomplete eradication of precancerous lesions contributes to interval colorectal cancer; therefore, alternative techniques for resection that safely and effectively increase the rate of complete resection are important. Underwater resection (UR) of benign colorectal lesions is a novel technique that utilizes the advantages of water aided endoscopic methods and may decrease the incomplete resection rate of small and large non-pedunculated lesions.

The investigators propose the hypothesis that small (6-9mm) and large (≥1cm) non-pedunculated neoplastic colorectal lesions resected by UR (partially distended, water filled lumen without submucosal fluid injection), will significantly decrease the incomplete resection rate (IRR) compared to conventional polypectomy performed in a gas distended lumen.

Small (6-9mm) and large (≥1cm) non-pedunculated benign neoplastic colorectal lesions identified during screening, surveillance, diagnostic or therapeutic colonoscopy will be randomized to conventional polypectomy (in a gas distended lumen with or without submucosal fluid injection) versus UR (partially distended, water filled lumen without submucosal injection) at the patient level. Small (6-9mm) lesions will be removed with a 9mm firm, thin wire cold snare and large (≥1cm) lesions will be removed by snare electrocautery. Efforts to remove lesions en bloc with a small rim of normal mucosa will be made, although some larger lesions (≥2cm) may require piecemeal resection. Submucosal fluid injection with a solution may be used with conventional techniques for large and/or flat lesions. Post-polypectomy incomplete resection rates will be assessed from 4 quadrant biopsies obtained around the resection site immediately post-resection.

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Conditions studied

  • Colorectal Neoplasms

Keywords

  • Colonoscopy
  • Polypectomy
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In context

Colorectal Neoplasms

5,598 studies on the registry are indexed under Colorectal Neoplasms; 1,458 are open to participants now.

This study's enrollment of 600 is above the median of 77 across 4,122 interventional studies indexed under Colorectal Neoplasms.

Browse Colorectal Neoplasms studies →

Lead sponsor

VA Northern California Health Care System is the lead sponsor of 7 studies on the registry; none are open to participants now.

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

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Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  • Adult (≥18 years old) male and female patients.
  • Scheduled for outpatient colonoscopy.
  • Patient able to provide informed consent.
  • Benign, small (6-9mm) and large (≥1cm) non-pedunculated colorectal lesions.

Exclusion criteria

Exclusion Criteria:

  • Diminutive (≤5mm) and pedunculated polyps.
  • Lesions suspected of harboring deep submucosal invasion.
  • Patients who decline to participate or are unable to provide informed consent.
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Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
600 participants (actual)

Study arms

  • Experimental
    Underwater resection

    All eligible lesion identified in a patient will be resected by the underwater technique. Excluded lesions will be resected by standard polypectomy.

    Procedure: Underwater resection · Procedure: Standard polypectomy

  • Active comparator
    Conventional resection

    All eligible lesion identified in a patient will be resected by the conventional (gas distended colon) resection techniques. Excluded lesions will be resected by standard polypectomy.

    Procedure: Conventional (gas distended colon) resection · Procedure: Standard polypectomy

Interventions

  • ProcedureUnderwater resection

    Underwater resection of eligible lesions will be performed with air exclusion (air will be suctioned and completely removed) without submucosal injection in a partially collapsed colon lumen filled with water. Water will be infused with the foot pedal to facilitate visualization during UR and there will be no limit to the amount of water infused. Hot and cold resection techniques will be utilized.

  • ProcedureConventional (gas distended colon) resection

    Conventional polypectomy of eligible lesions will be performed in a gas distended colon. Hot and cold resection techniques will be utilized. Submucosal fluid injection with a solution containing hydroxyethyl starch, dilute epinephrine and a contrast agent may be used with conventional techniques for large (≥1cm) and/or flat lesions. There will be no limit to the amount of submucosal injection used.

  • ProcedureStandard polypectomy

    Standard polypectomy will be performed for diminutive (\<6mm), pedunculated and semi-pedunculated lesions that do not fall under the inclusion criteria for the study. These lesions will be removed in a gas distended colon with a 9mm firm, thin wire cold snare or snare electrocautery for large (≥1cm) lesions.

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What researchers measure

Primary outcomes

  1. Incomplete resection rate (histologic)

    Time frame: 24 months

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Study locations

1 site
  • Sacramento VA Medical Center (VANCHCS)
    Mather, California 95655, United States
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References and documents

Publications

  • Pohl H, Srivastava A, Bensen SP, Anderson P, Rothstein RI, Gordon SR, Levy LC, Toor A, Mackenzie TA, Rosch T, Robertson DJ. Incomplete polyp resection during colonoscopy-results of the complete adenoma resection (CARE) study. Gastroenterology. 2013 Jan;144(1):74-80.e1. doi: 10.1053/j.gastro.2012.09.043. Epub 2012 Sep 25. Erratum In: Gastroenterology. 2021 Oct;161(4):1347. doi: 10.1053/j.gastro.2021.08.018. PubMed 23022496 ↗
  • Binmoeller KF, Weilert F, Shah J, Bhat Y, Kane S. "Underwater" EMR without submucosal injection for large sessile colorectal polyps (with video). Gastrointest Endosc. 2012 May;75(5):1086-91. doi: 10.1016/j.gie.2011.12.022. Epub 2012 Feb 25. PubMed 22365184 ↗
  • Yen AW, Leung JW, Wilson MD, Leung FW. Underwater versus conventional endoscopic resection of nondiminutive nonpedunculated colorectal lesions: a prospective randomized controlled trial (with video). Gastrointest Endosc. 2020 Mar;91(3):643-654.e2. doi: 10.1016/j.gie.2019.09.039. Epub 2019 Oct 16. PubMed 31628954 ↗

Individual participant data

Plan to share: No

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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Dec 20, 2018, 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
NCT02889679
Lead sponsor
VA Northern California Health Care System
Responsible party
Sponsor
First posted
Sep 5, 2016
Start date
Sep 2016
Primary completion
Oct 2018
Completion
Oct 2018
Last update
Dec 20, 2018

Study contacts

Andrew W Yen, MD
principal investigator · VA Northern California Health Care System

Oversight

Data monitoring committee
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Dec 2018. You cannot join it, but the record below documents what was studied.

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