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Cited by 211Colorectal Cancer Screening and DetectionGenetic factors in colorectal cancerAI in cancer detection

Narrow band imaging optical diagnosis of small colorectal polyps in routine clinical practice: the Detect Inspect Characterise Resect and Discard 2 (DISCARD 2) study

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Rees, Colin J, Rajasekhar, Praveen T, Wilson, Ana, Close, Helen, Rutter, Matthew D, Saunders, Brian P, East, James E, Maier, Rebecca +8 more·2017·Gut
DOI 10.1136/gutjnl-2015-310584PMC PMC5531217
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Abstract

BACKGROUND: Accurate optical characterisation and removal of small adenomas (<10 mm) at colonoscopy would allow hyperplastic polyps to be left in situ and surveillance intervals to be determined without the need for histopathology. Although accurate in specialist practice the performance of narrow band imaging (NBI), colonoscopy in routine clinical practice is poorly understood. METHODS: NBI-assisted optical diagnosis was compared with reference standard histopathological findings in a prospective, blinded study, which recruited adults undergoing routine colonoscopy in six general hospitals in the UK. Participating colonoscopists (N=28) were trained using the NBI International Colorectal Endoscopic (NICE) classification (relating to colour, vessel structure and surface pattern). By comparing the optical and histological findings in patients with only small polyps, test sensitivity was determined at the patient level using two thresholds: presence of adenoma and need for surveillance. Accuracy of identifying adenomatous polyps <10 mm was compared at the polyp level using hierarchical models, allowing determinants of accuracy to be explored. FINDINGS: Of 1688 patients recruited, 722 (42.8%) had polyps <10 mm with 567 (78.5%) having only polyps <10 mm. Test sensitivity (presence of adenoma, N=499 patients) by NBI optical diagnosis was 83.4% (95% CI 79.6% to 86.9%), significantly less than the 95% sensitivity (p<0.001) this study was powered to detect. Test sensitivity (need for surveillance) was 73.0% (95% CI 66.5% to 79.9%). Analysed at the polyp level, test sensitivity (presence of adenoma, N=1620 polyps) was 76.1% (95% CI 72.8% to 79.1%). In fully adjusted analyses, test sensitivity was 99.4% (95% CI 98.2% to 99.8%) if two or more NICE adenoma characteristics were identified. Neither colonoscopist expertise, confidence in diagnosis nor use of high definition colonoscopy independently improved test accuracy. INTERPRETATION: This large multicentre study demonstrates that NBI optical diagnosis cannot currently be recommended for application in routine clinical practice. Further work is required to evaluate whether variation in test accuracy is related to polyp characteristics or colonoscopist training. TRIAL REGISTRATION NUMBER: The study was registered with clinicaltrials.gov (NCT01603927).

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  • The limited clinical uptake of diagnose-and-leave and resect-and-discard strategies is due to their suboptimal accuracy.

    “However, the limited clinical uptake of these strategies is due to their suboptimal accuracy.3-6”

    From Structured Integration of an Artificial Intelligence-Based System for the Optical Diagnosis of Colorectal Polyps (2026) · cites this paper as [6]

    The Discussion (page unavailable) finds that optical diagnosis by non-experts was not accurate enough to replace histology, and the clinical-practice section says it cannot currently be recommended for routine use. These passages support suboptimal accuracy as a barrier, but the paper does not establish that limited clinical uptake of both strategies is due to that cause. (LLM, conf=0.84)

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Authors
Rees, C. J., Rajasekhar, P. T., Wilson, A., Close, H., Rutter, M. D., Saunders, B. P., East, J. E., Maier, R., Moorghen, M., Muhammad, U., Hancock, H., Jayaprakash, A., MacDonald, C., Ramadas, A., Dhar, A., & Mason, J. M.
Affiliations
  • Durham University (GB)
  • South Tyneside District Hospital (GB)
  • London North West Healthcare NHS Trust (GB)
  • North Tees and Hartlepool NHS Foundation Trust (GB)
  • John Radcliffe Hospital (GB)
  • Northumbria Healthcare NHS Foundation Trust (GB)
  • South Tees Hospitals NHS Foundation Trust (GB)
  • County Durham and Darlington NHS Foundation Trust (GB)
  • University of Warwick (GB)
Corresponding author
Rees, Colin J
ORCID
Venue
Gut
Publisher
BMJ
Published
2016-04-19
Volume
66
Issue
5
Pages
887-895
ISSN
  • 0017-5749 (ISSN-L)
  • 1468-3288
DOI
10.1136/gutjnl-2015-310584
PMC
PMC5531217
OpenAlex
W2338997131
Cited by
211
References
1
Citations by year
2026: 8 · 2025: 15 · 2024: 19 · 2023: 20 · 2022: 27 · 2021: 23 · 2020: 27 · 2019: 23 · 2018: 25 · 2017: 18 · 2016: 4 · 2014: 1
FWCI
10.65
Type
journal article
Language
en
Open access
Licence
cc-by-nc
Locations
  • Gut (publishedVersion, cc-by-nc)
  • PubMed Central (publishedVersion, cc-by-nc)
  • PubMed (publishedVersion)
  • Warwick Research Archive Portal (University of Warwick) (acceptedVersion)
  • Durham Research Online (Durham University) (acceptedVersion, other-oa)
  • Oxford University Research Archive (ORA) (University of Oxford) (acceptedVersion)
  • Durham Research Online (Durham University) (submittedVersion, cc-by-nc)
  • HighWire Press Open Archive (submittedVersion)
  • Newcastle University ePrints (Newcastle Univesity) (cc-by-nc)
Funders
  • National Institute for Health and Care Research (PB-PG-0407-13309)
  • Research for Patient Benefit Programme
Topics
  • Health Sciences › Medicine › Oncology › Colorectal Cancer Screening and Detection
  • Health Sciences › Medicine › Pathology and Forensic Medicine › Genetic factors in colorectal cancer
  • Physical Sciences › Computer Science › Artificial Intelligence › AI in cancer detection
Keywords
narrow-band imaging, small colorectal polyps, optical diagnostics, adenoma detection, hyperplastic polyps, colonoscopy, NICE classification, surveillance interval, histopathological validation, routine clinical practice, high-definition colonoscopy, colorectal cancer prevention
MeSH terms
Adenoma, Aged, Clinical Competence, Colonic Polyps, Colonoscopy, Double-Blind Method, Female, Humans, Male, Middle Aged, Population Surveillance, Prospective Studies, Sensitivity and Specificity, Time Factors, Colorectal Neoplasms, Observer Variation, Narrow Band Imaging

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