Endoscopic Classifications of Early Gastric Cancer: A Literature Review

Abstract

Endoscopic technologies have been continuously advancing throughout the years to facilitate improvement in the detection and diagnosis of gastric lesions. With the development of different endoscopic diagnostic modalities for EGC, several classifications have been advocated for the evaluation of gastric lesions, aiming for an early detection and diagnosis. Sufficient knowledge on the appearance of EGC on white light endoscopy is fundamental for early detection and management. On the other hand, those superficial EGC with subtle morphological changes that are challenging to be detected with white light endoscopy may now be clearly defined by means of image-enhanced endoscopy (IEE). By combining magnifying endoscopy and IEE, irregularities in the surface structures can be evaluated and highlighted, leading to improvements in EGC diagnostic accuracy. The main scope of this review article is to offer a closer look at the different classifications of EGC based on several endoscopic diagnostic modalities, as well as to introduce readers to newer and novel classifications, specifically developed for the stomach, for the assessment and diagnosis of gastric lesions.

Evaluation of the detection rate of high‑grade gastric intraepithelial neoplasia using linked color imaging and white light imaging

“…Following years of research, a consensus on the utility of endoscopy for gastric cancer diagnosis has been reached, along with recommendations to reduce Helicobacter pylori infections, take sufficient exercise and follow a healthy lifestyle (18). The early detection of gastric cancer increases the likelihood of treatments being effective (19)(20)(21).…”

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

“…Nevertheless, it has distinct limitations: considerable is required for image acquisition, there is a steep learning curve associated with image interpretation, and the required equipment is typically available only at tertiary care centers (46). 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).…”

“…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).…”

Comprehensive analysis regarding the prognostic significance of downregulated ferroptosis-related gene AKR1C2 in gastric cancer and its underlying roles in immune response

“…Gastric cancer (GC), as one of the most common malignant tumors in the world, ranks the fifth most diagnosed cancer worldwide [ 1 ]. Nowadays, several therapeutic strategies have been reported to be effective in the treatment of GC patients, including surgical treatment, chemotherapy, and immunotherapy [ 2 ].…”