Usefulness of Demarcation of Differentiated-Type Early Gastric Cancers after Helicobacter pylori Eradication by Magnifying Endoscopy with Narrow-Band Imaging.

BACKGROUND/AIMS: Early gastric cancer after Helicobacter pylori (Hp) eradication is difficult to demarcate. We used the vessel plus surface classification system (VSCS) to determine whether magnifying endoscopy with narrow-band imaging (ME-NBI) could demarcate differentiated-type early gastric cancers after Hp eradication, and to identify causes of an unclear demarcation line (DL). METHODS: Among 100 lesions of differentiated-type early gastric cancer resected endoscopically, 34 lesions in the Hp-eradicated group and 66 in the Hp-infected group were retrospectively compared. Clinicopathological factors and ME-NBI findings, including the presence or absence of the DL, were examined. Histopathologically, histological gastritis, the surface structure at the tumor border, well-differentiated adenocarcinoma with low-grade atypia (tub1-low), and non-neoplastic epithelium (NE) coverage rate on the tumor surface and at the tumor border were evaluated. RESULTS: DL (-) cases were more frequent in the Hp-eradicated group (11.8%, 4/34) than in the Hp-infected group (1.5%, 1/66; p < 0.05). The Hp-eradicated group had a higher NE coverage rate than the Hp-infected group (p < 0.05). All DL (-) cases had tub1-low or NE at the tumor border. CONCLUSION: ME-NBI with VSCS can identify the DL in most patients (88.2%) with differentiated-type early gastric cancer after Hp eradication.