Emergence of a New Optical Marker for Colorectal Neoplasms: To What Extent Should We Accept It?

Han Hee Lee; Hisabe Takashi

doi:10.5946/ce.2021.264

Articles

Page Path: HOME > Clin Endosc > Volume 55(2); 2022 > Article

Letter to the Editor Emergence of a New Optical Marker for Colorectal Neoplasms: To What Extent Should We Accept It?: Han Hee Lee, Hisabe Takashi; Clinical Endoscopy 2022;55(2):315-317.
DOI: https://doi.org/10.5946/ce.2021.264
Published online: February 21, 2022

Division of Gastroenterology, Department of Internal Medicine College of Medicine, The Catholic University of Korea Seoul, Korea

Department of Gastroenterology Fukuoka University Chikushi Hospital Fukuoka, Japan

Correspondence: Han Hee Lee Division of Gastroenterology, Department of Internal Medicine, Yeouido St. Mary’s Hospital College of Medicine, The Catholic University of Korea, 10, 63-ro, Yeongdeungpo-gu, Seoul 07345, Republic of Korea Tel: +82-2-3779-1519, Fax: 682-2-3779-1331, E-mail: hanyee99@hanmail.net

• Received: October 22, 2021 • Revised: November 15, 2021 • Accepted: November 16, 2021

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

2,807 Views
125 Download

Full Article

Download PDF

NOTES
REFERENCES
NOTES
REFERENCES

To the Editor:

Colorectal cancer (CRC) is among the most common cancers worldwide whose incidence and prevalence have been increasing, especially among subjects younger than 50 years of age [1]. Colonoscopy is considered the most sensitive and effective CRC screening method as well as an essential prevention strategy because it can be used to detect and remove premalignant adenomas. Furthermore, the introduction of high-definition and magnifying endoscopy has increased adenoma detection rates and made it possible to predict CRC histological results and invasion depth [2]. The Japan NBI Expert Team (JNET) classification, which is accepted as the NBI magnifying classification standard, classifies tumors into four types according to surface and vessel patterns: 1, 2A, 2B, and 3 [3]. Type 2B ranges from high-grade dysplasias to superficial submucosal invasive (SM-s) carcinomas. However, the actual diagnostic performance of type 2B is so weak that 37% and 12% of type 2B lesions were identified as low-grade dysplasia and deep submucosal invasive (SM-d) carcinoma, respectively [4]. The accurate prediction of histological findings through endoscopic examinations can enable the selection of the correct endoscopic resection method and reduce non-curative resection rates, thereby reducing unnecessary subsequent management efforts and the risk of poor outcomes such as recurrence [5,6].

I received inspiration from an article on the usefulness of white opaque substances (WOS) in colorectal epithelial neoplasms observed during magnifying endoscopy. Yamasaki et al. reported that irregular WOS are useful predictors of early colorectal carcinoma with an accuracy, sensitivity, and specificity of 87%, 91%, and 86%, respectively [7]. Notably, the presence of WOS is a relatively objective indicator with a 96% negative predictive value for carcinoma. However, endoscopists must consider several points before using WOS as a new optical marker. First, a significant number of colorectal epithelial neoplasms do not feature WOS. More than half of the 511 initially recruited lesions were WOS-negative, and 72 of the remaining 197 neoplastic lesions included WOS in less than half of the area under maximal magnification endoscopy, making them unsuitable for analysis. This phenomenon may be due to the characteristics of a retrospective study evaluating recorded endoscopic images only because it is unknown how many WOS-positive cases will emerge in a prospective study. Second, WOS showed poor performance for discriminating between SM-d carcinoma and superficial carcinoma (p=0.727) cases, making it a less suitable option because the most important objective of magnifying endoscopy is predicting SM-d carcinoma. Therefore, to distinguish between SM-d carcinoma and superficial carcinoma cases, it is necessary to observe the pit pattern using traditional chromoendoscopy. In conclusion, WOS can currently play only an auxiliary role in the observation of surface patterns, and the accumulation of more data is required to determine the clinical significance of the presence of WOS.

Conflicts of Interest: The author has no potential conflicts of interests.

Funding

This research was supported by the Bio & Medical Technology Development Program of the National Research Foundation (NRF) funded by the Ministry of Science & ICT (NRF-2018M3A9E8021507).

REFERENCES

1. Kim JY, Choi S, Park T, et al. Development and validation of a scoring system for advanced colorectal neoplasm in young Korean subjects less than age 50 years. Intest Res 2019;17:253–264.Article PubMed
2. Gonai T, Kawasaki K, Nakamura S, et al. Microvascular density under magnifying narrow-band imaging endoscopy in colorectal epithelial neoplasms. Intest Res 2020;18:107–114.Article PubMed
3. Sano Y, Tanaka S, Kudo SE, et al. Narrow-band imaging (NBI) magnifying endoscopic classification of colorectal tumors proposed by the Japan NBI Expert Team. Dig Endosc 2016;28:526–533.Article PubMed
4. Sumimoto K, Tanaka S, Shigita K, et al. Diagnostic performance of Japan NBI Expert Team classification for differentiation among noninvasive, superficially invasive, and deeply invasive colorectal neoplasia. Gastrointest Endosc 2017;86:700–709.Article PubMed
5. Choi YS, Kim WS, Hwang SW, et al. Clinical outcomes of submucosal colorectal cancer diagnosed after endoscopic resection: a focus on the need for surgery. Intest Res 2020;18:96–106.Article PubMed PMC
6. Park J, Kim HG, Jeong SO, et al. Clinical outcomes of positive resection margin after endoscopic mucosal resection of early colon cancers. Intest Res 2019;17:516–526.Article PubMed PMC
7. Yamasaki K, Hisabe T, Yao K, et al. White opaque substance, a new optical marker on magnifying endoscopy: usefulness in diagnosing colorectal epithelial neoplasms. Clin Endosc 2021;54:570–577.Article PubMed PMC

We thank Dr. Han Hee Lee for their interest in our recent manuscript [1].

First, since this was our first investigation of white opaque substances (WOS) morphology, it was unclear whether the morphology of WOS was useful for qualitative diagnosis. Therefore, in this study, we focused on cases where the morphology of WOS could be clearly determined and we included WOS-positive lesions in which WOS was present in more than half the area at maximum magnification. Currently, we are able to evaluate the morphology of WOS that are present in less than half the area.

Second, as Dr. Lee pointed out, WOS did not show good performance in discriminating between deep submucosal invasive (SM-d) carcinoma and superficial carcinoma. If the surface pattern and vessel pattern cannot be seen by narrow band imaging with magnifying endoscopy due to the presence of WOS, it cannot be applied to the Japan NBI Expert Team (JNET) classification. We believe that the morphology of WOS is very useful for the differential diagnosis between adenoma and carcinoma when the surface pattern and vessel pattern are not visible. Although WOS has not been adopted as a marker in the current JNET classification, we reported it as a reproducible marker for surface pattern.

Conflicts of Interest: The author has no potential conflicts of interests.

Funding:None.

REFERENCES

1. Yamasaki K, Hisabe T, Yao K, et al. White opaque substance, a new optical marker on magnifying endoscopy: usefulness in diagnosing colorectal epithelial neoplasms. Clin Endosc 2021;54:570–577.Article PubMed PMC

Figure & Data

REFERENCES

Citations

Citations to this article as recorded by

PubReader
ePub Link

Cite

CITE: export Copy Download Format; Close

Download Citation

Download a citation file in RIS format that can be imported by all major citation management software, including EndNote, ProCite, RefWorks, and Reference Manager.