Current progress toward eradicating Helicobacter pylori in East Asian countries: Differences in the 2013 revised guidelines between China, Japan, and South Korea

Figure 1 Changes in serum pepsinogen levels according to the progress of gastric carcinogenesis. The pepsinogen II level is increased in the acute stage of Helicobacter pylori (H. pylori) infection. A pepsinogen II level exceeding 30 ng/dL indicates that the subject has a high risk of diffuse-type gastric cancer. The pepsinogen I level then decreases as the infection progresses to the chronic stage. These features altogether results in the pepsinogen I/II ratio decreasing with the progress of gastric carcinogenesis. A pepsinogen I level below 70 ng/dL and a pepsinogen I/II ratio below 3.0 indicate that the subject has a high risk of intestinal-type gastric cancer. Since the pepsinogen II level is decreased after H. pylori eradication to a variable degree, a combination test for serum H. pylori antibody and the pepsinogen I/II ratio is not recommended for gastric cancer screening after eradication.

Figure 2 Metachronous gastric cancer that developed after 6 years of Helicobacter pylori eradication. A 61 year-old South Korean man visited because of epigastric discomfort in March 2007. A: Initial endoscopic finding. Several raised erosions with central ulceration (arrow) were evident. Since H. pylori infection was found by gastric biopsy, eradication was achieved using amoxicillin (1 g), clarithromycin (500 mg), and a a standard dose of proton pump inhibitor twice daily for 7 d; B: Endoscopic finding after 2 years. In June 2009, a gastric adenoma near the pylorus (arrow) was diagnosed by endoscopic biopsy. Complete endoscopic resection was performed; C: Immunohistochemical staining of the resected specimen. Ki-67 staining was positive in the adenoma (Ki-67 stain, x 400); D: Endoscopic finding after 6 years. In January 2013, a slightly depressed lesion was evident on the lesser curvature side of the mid-antrum (arrow); E: Endoscopic submucosal dissection. The lesion was resected since the endoscopic biopsy revealed an adenocarcinoma; F: Pathological finding of the resected specimen. Early gastric cancer type IIc of Lauren’s intestinal-type, moderately-differentiated, tubular adenocarcinoma was diagnosed. The tumor size was 8.0 mm x 6.0 mm x 1.0 mm, and the depth of invasion was limited to the lamina propria (pT1a). Resection margins were free from carcinoma.