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.

Keywords: classification; diagnosis; early gastric cancer; endocytoscopy; endoscopy; magnifying endoscopy; narrow band imaging.

Figure 1

Representative images of the Paris endoscopic classification (upper row: white light only, lower row: same lesions under chromoendoscopy).

Figure 2

Magnifying endoscopy simple diagnostic algorithm for early gastric cancer (MESDA-G) [22].

Figure 3

Gastric UMEC: (A) UMEC 1/2A is considered as non-cancer and (B) UMEC 2B/3 is considered as cancer.

Figure 4

EC Classification: (A) EC1 is considered as non-neoplastic, with regularly arranged glands, well-preserved lumen, and poorly stained nuclei; (B) EC2 is considered as adenoma, with a more compact glandular arrangement, lumen narrowing and poorly stained nuclei; and (C) EC3 is considered as carcinoma with distorted glandular structure and enlarged nuclear sign. The border between the background mucosa and the cancerous area can be noted in this photo.