Endoscopic Diagnosis of Barrett's Esophagus and Esophageal Adenocarcinomas

The use of methylene blue and acetic acid in magnifying endoscopic diagnosis of intestinal metaplasia in Barrett's esophagus has been reported previously. Recently, the use of acetic acid or narrow-band imaging (NBI) has been described in magnifying endoscopic diagnosis of intramucosal adenocarcinomas arising from Barrett's esophagus. Diagnosis by NBI is based on the examination of microvascular patterns. The characteristic microvascular patterns of intramucosal adenocarcinomas in Barrett's esophagus are the mesh pattern and the loop pattern. The former appears on the lesion with dense round pits and the latter tend to appear oil the lesion with elongated cancerous crypts. Acetic acid is used in the two methods of magnifying endoscopic diagnosis of adenocarcinoma: enhanced-magnification endoscopy and dynamic chemical magnifying endoscopy. In the former, the structure of the mucosal surface is observed after enhancement of the surface color with acetic acid to a clear white. In the latter, the difference between cancerous and noncancerous lesions is observed on the basis of the difference in duration of the whitening. These magnified views are very clear and facilitate the accurate diagnosis of cancerous lesions that are difficult to diagnose by conventional endoscopy. Because they help delineate the extent of cancerous lesions, these new methods of diagnosis support curative surgery of adenocarcinoma in Barrett's esophagus by endoscopic submucosal dissection.