Endocytoscopy: technology and clinical application in upper gastrointestinal tract

Abstract

Over the past few years, the innovative field of magnifying endoscopy has been expanding with various cutting-edge technologies, one of which is endocytoscopy, to facilitate improvement in the detection and diagnosis of gastrointestinal lesions. Endocytoscopy is a novel ultra-high magnification endoscopic technique enabling high-quality in-vivo assessment of lesions found in the gastrointestinal tract with the use of intraprocedural stains. The main scope of this review article is to offer a closer look at the latest endocytoscopic technology and its clinical application in the upper gastrointestinal tract, especially in the esophagus and stomach, as well as to introduce readers to our simplified and up-to-date endocytoscopic classification, specifically developed for the esophagus and stomach, for the in-vivo assessment and diagnosis of esophageal and gastric lesions. Despite the good accuracy of endocytoscopy in the diagnosis of esophageal and gastric lesions in recent studies, some challenges still remain (e.g., staining method and standardized endocytoscopic classification). Through continuous evaluation and improvement of methods and skills, these challenges may be overcome thus establishing current techniques and classification, paving the way for further advances in the field of endocytoscopy and magnifying endoscopy. In all, endocytoscopy seems to aid in the in-vivo diagnosis of gastrointestinal tract lesions and may, in the future, revolutionize the field of in-vivo endoscopic diagnosis of gastrointestinal cancer, representing another step towards the so-called optical biopsy.

Research trends in endoscopic applications in early gastric cancer: A bibliometric analysis of studies published from 2012 to 2022

“…Endocytoscopy (EC) is one of the most sophisticated current techniques, based on ultra-high magnification endoscopy, and allows the in vivo microscopic visualization of the surface level of mucosal cells with the use of stains (8,47). Fourth-generation endocytoscopes support 500× continuous zoom-focus magnification, and the average time needed to conduct EC is approximately 10-20 minutes (48). Standardized classification criteria for EC-detected stomach cancer are not yet in place; however, in another study, Inoue Haruhiro et al (8,48,49) developed a simple, three-level, classification of EC-detected colorectal lesions (50): non-neoplastic lesions are classified as EC1, adenoma is classified as EC2, and carcinoma is classified as EC3 (8).…”

“…Fourth-generation endocytoscopes support 500× continuous zoom-focus magnification, and the average time needed to conduct EC is approximately 10-20 minutes (48). Standardized classification criteria for EC-detected stomach cancer are not yet in place; however, in another study, Inoue Haruhiro et al (8,48,49) developed a simple, three-level, classification of EC-detected colorectal lesions (50): non-neoplastic lesions are classified as EC1, adenoma is classified as EC2, and carcinoma is classified as EC3 (8). Furthermore, they identified an "enlarged nuclear sign"(ENS) as a distinct characteristic of gastric adenocarcinomas and reported that the sensitivity, specificity, and accuracy of ENS for the diagnosis of EGC were 84.8%, 90.0%, and 87.2%, respectively (49).…”

Endoscopic Classifications of Early Gastric Cancer: A Literature Review

“…In this classification, structural and cellular atypia, such as lumen morphology and nuclear changes, were assessed to differentiate between non-neoplastic (EC1a and EC1b), and neoplastic (EC2, EC3a, EC3b). By adopting this classification, our group developed a simplified EC classification for the diagnosis of gastric lesions [ 32 , 33 ]. In our simplified classification, we assess the glandular pattern, lumen, and nuclear changes to differentiate between non-neoplastic (EC1), adenoma (EC2), and carcinoma (EC3) ( Figure 4 ).…”

Use of topical methylene blue to image nuclear morphometry with a low-cost scanning darkfield microendoscope

“… 16 , 17 In addition, MB is FDA-approved for intravenous administration to treat methemoglobinemia. 13 Numerous clinical studies have demonstrated in vivo application of MB on human subjects for macroscopic examination of oral precancerous lesions, 18 , 19 endocytoscopy, 20 , 21 and surgical guidance. 22 MB has been verified in these studies as a safe contrast agent with significant potential for broader acceptance in clinical uses.…”