The Incremental Benefit of Dye Chromoendoscopy Compared to High-Definition White Light and Virtual Chromoendoscopy for Lesion Assessment and Prediction of Submucosal Invasion - European Medical Journal

The Incremental Benefit of Dye Chromoendoscopy Compared to High-Definition White Light and Virtual Chromoendoscopy for Lesion Assessment and Prediction of Submucosal Invasion

1 Mins
Gastroenterology
EMJ Gastroenterology 9.1 2020 Feature Image
Authors:
*Mayenaaz Sidhu,1,2 Neal Shahidi,1,2,3 Sergei Vosko,1 W. Arnout van Hattem,1 David J. Tate,1,4 Michael J. Bourke1,2
Disclosure:

Dr Bourke reports having research funding support from Olympus Corporation, Boston Scientific Corporation, Cook Medical Incorporated. The other authors have declared no conflicts of interest.

Citation:
EMJ Gastroenterol. ;9[1]:52-53. Abstract Review No. AR5.
Keywords:
Adenoma, cancer, colonoscopy, endoscopy, polyp, tumour.

Each article is made available under the terms of the Creative Commons Attribution-Non Commercial 4.0 License.

BACKGROUND AND AIMS

The identification of a demarcated area (DA), where a regular microvascular or pit pattern appears disordered, is a fundamental principle of optical evaluation and can predict the presence of submucosal invasive cancer (SMIC) in large (≥20 mm) nonpedunculated colorectal polyps (LNPCP).1-3 While virtual chromoendoscopy (VCE) is the primary method for performing optical evaluation, it has shown modest performance for LNPCP. Dye-based chromoendoscopy (DBC) is an alternative which has shown excellent performance characteristics with traditional magnification.4 The authors therefore sought to evaluate the incremental benefit of DBC in addition to high-definition white light (HDWL) and VCE for DA identification and the prediction of SMIC in LNPCP.

METHODS

A prospective observational study of consecutive LNPCP at a single tertiary referral centre was performed.5Prior to resection, all LNPCP were initially assessed for a DA with HDWL plus VCE (Narrow Band Imaging [Olympus Corporation, Tokyo, Japan]) and then by DBC, by two trained independent observers. DA diagnostic performance (sensitivity, specificity, positive predictive value, and negative predictive value) and interobserver agreement (k statistic) were calculated.

RESULTS

Over 22 months to September 2019, 205 consecutive LNPCP (median size: 38mm; interquartile range: 30-50 mm; 46.8% right colon) were enrolled. The overall frequency of SMIC was 9.3%. The absence of a DA had a negative predictive value of 95.6% (95% confidence interval: 92.2–97.6%) for SMIC, independent of the use of DBC. A high rate of interobserver agreement was recorded for the identification of a DA with HDWL plus VCE (99.5%; k=0.98) and with HDWL plus VCE plus DBC (99%; k=0.95).

DISCUSSION

Lesion assessment is a critical component in determining the suitability of endoscopic resection for LNPCP.6-8 In this study, the authors demonstrated that the use of HDWL combined with VCE had a high rate of interobserver agreement for DA identification, independent of the use of DBC. More importantly, they showed that the absence of a DA on the surface of LNPCP is a very strong predictor for the absence of SMIC, also independent of the use of DBC. Taken together, there is no role for the universal application of DBC in addition to HDWL plus VCE for LNPCP. Moreover, the results supported that LNPCP not demonstrating a DA, and in absence of lesion characteristics associated covert SMIC, can be safely resected by piecemeal endoscopic mucosal resection. These study findings do require validation outside of an expert setting and provide an avenue for future research.

CONCLUSION

In conclusion, the absence of a DA within LNPCP is strongly predictive for the absence of SMIC. It can be determined without the need for DBC with a high rate of interobserver agreement among experts.

References
Puig I et al.; EndoCAR group, Spanish Gastroenterological Association and the Spanish Digestive Endoscopy Society. Accuracy of the narrow-band imaging international colorectal endoscopic classification system in identification of deep invasion in colorectal polyps. Gastroenterology. 2019;156(1):75-87. Backes Y et al. Narrow band imaging, magnifying chromoendoscopy, and gross morphological features for the optical diagnosis of T1 colorectal cancer and deep submucosal invasion: a systematic review and meta-analysis. Am J Gastroenterol. 2017;112(1):54-64. Matsuda T et al. Efficacy of the invasive/non-invasive pattern by magnifying chromoendoscopy to estimate the depth of invasion of early colorectal neoplasms. Am J Gastroenterol. 2008;103(11):2700-6. Kudo S et al. Colorectal tumours and pit pattern. J Clin Pathol. 1994;47(10):880-5. Western Sydney Local Health District. Comparison of the benefit of chromoendoscopy in addition to high definition white light and narrow band imaging for the prediction of submucosal invasive cancer in colonic lesions (LANS). NCT03506321. https://clinicaltrials.gov/ct2/show/NCT03506321. Shahidi N et al. Optical evaluation: the crux for effective management of colorectal neoplasia. Therap Adv Gastroenterol. 2020;13:1-18. Moss A et al. Long-term adenoma recurrence following wide-field endoscopic mucosal resection (WF-EMR) for advanced colonic mucosal neoplasia is infrequent: results and risk factors in 1000 cases from the Australian Colonic EMR (ACE) study. Gut. 2015;64(1):57-65. Puig I et al. Endoscopic imaging techniques for detecting early colorectal cancer. Curr Opin Gastroenterol. 2019; 35(5):432-9.

Rate this content's potential impact on patient outcomes

Thank you!

Please share some more information on the rating you have given