Fig. 1. Flow diagram of the patient enrollment process. ER, endoscopic resection; BEA, Barrett’s esophageal adenocarcinoma.

Fig. 2. (A) Endoscopic image of Barrett’s esophageal adenocarcinoma (BEA) in the clear demarcation group. (B) Magnifying endoscopy with narrow-band imaging show clear demarcation of the lesion. (C) Endoscopic image of BEA in the unclear demarcation group. (D) Magnifying endoscopy with narrow-band imaging show mild irregularity of the lesion and unclear demarcation of the lesion.

Fig. 3. Evaluation of the pathological structures. (A) A representative slide displaying the demarcation of the lesion. Black arrow indicates the demarcation between cancerous and non-cancerous area (hematoxylin and eosin stain, ×40). (B) This figure specifically illustrates the length and width of foveolar structures and the width of marginal crypt epithelium.

Fig. 4. A representative case from the unclear demarcation group. (A) The reddish depressed lesion are seen at the anterior side of the esophagogastric junction. (B) Magnifying endoscopy with narrow-band imaging show mild irregular mucosal pattern, and the demarcation of the lesion is unclear. However, there is a distinct difference in the width of marginal crypt epithelium (MCE) between the mucosa on the upper and lower part of this image; the MCE appears narrower on the upper part and wider on the lower, which corresponds to the cancerous mucosa and non-cancerous mucosa, respectively. (C) Pathological findings reveal significant difference in the width of MCE between cancerous and non-cancerous area. Black arrows indicate the edge of MCE, and thus the area sandwiched by black arrows shows the width of MCE.

Fig. 5. Newly proposed magnified endoscopic classification of Barrett's esophageal neoplasms, incorporating the results of this study. GTV, green thick vessels; m-FP, modified flat pattern; MCE, marginal crypt epithelium.

Graphical abstract