Barrett's esophageal cancer in which magnifying narrow‐band imaging was useful for diagnosing extension under the squamous epithelium

A 36‐year‐old man complained of heartburn. Gastrointestinal endoscopies showed a reddish and slightly depressed lesion in the right‐anterior wall of the esophagogastric junction. With white light imaging, the area of the adenocarcinoma under the squamous epithelium was difficult to detect, but a slightly flat, elevated lesion appeared in the area of adenocarcinoma under the squamous epithelium. With narrow‐band imaging (NBI) in the area of the Barrett's esophageal cancer under the squamous epithelium, a slight, brownish change could be observed. In addition, with the magnifying technique, irregular mesh‐like vessels were observed, suggesting the presence of differentiatedadenocarcinoma under the squamous epithelium. The lesion was resected en bloc by endoscopic submucosal dissection, and Barrett's esophageal cancer under the squamous epithelium was histologically confirmed. In this case, NBI with magnifying endoscopy was very useful to diagnose the extension of Barrett's esophageal cancer under the squamous epithelium.