Because endoscopic submucosal dissection (ESD) of gastric cancer can only be curative if the cancer is detected at an early stage and a precise preoperative diagnosis is made, we reviewed the detection and characterization of early gastric cancer (EGC) using both conventional endoscopy with white-light imaging (C-WLI) and image-enhanced endoscopy (chromoendoscopy [CE] and magnifying narrow-band imaging [M-NBI]). Systematic screening of the stomach by C-WLI after ideal preparation of the patient is important for detecting a mucosal lesion, which can then be characterized using CE. However, a limitation of C-WLI with CE is the diagnosis of flat or small gastric cancers. To overcome this, M-NBI together with a comprehensive diagnostic system, termed the 'vessel plus surface classification' system, was developed and has proven very useful. Preoperative assessment for ESD involves determining: (i) histological type; (ii) size; (iii) depth of invasion; (iv) presence or absence of associated ulceration; and (v) horizontal extent of the cancer. A limitation of endoscopic diagnosis using M-NBI is the histologically undifferentiated type of carcinoma, in which case the biopsy specimen is used to make a histopathological diagnosis.
© 2013 The Authors. Digestive Endoscopy © 2013 Japan Gastroenterological Endoscopy Society.