Recent advancement in endoscopic diagnosis for risk stratification of gastric cancer.

Approximately 90% of cases of gastric cancer (GC) are caused by Helicobacter pylori infection, and screening esophagogastroduodenoscopy is effective for secondary prevention of GC. Endoscopic findings of the stomach due to H. pylori infection vary widely, and the risk of GC varies according to each finding. GC risk is evaluated by combining endoscopic and histopathological findings. In the operative link on gastritis assessment and operative link on gastric intestinal metaplasia assessment staging, GC risk is determined by histopathological evaluation. In the endoscopic grading of gastric intestinal metaplasia, Kyoto classification, and modified Kyoto classification, the risk is considered based on endoscopic findings. However, evaluating endoscopic findings is challenging because the evaluation varies depending on the skill of the endoscopist. Similarly, histopathological findings can be assessed differently by different pathologists. Histopathological evaluation by biopsy carries a risk of bleeding; thus, simpler and less-invasive risk stratification methods are desirable. Artificial intelligence for risk stratification, which has the potential for improved accuracy and consistency, has been developed for endoscopic and histopathological evaluations. Appropriate GC risk stratification would benefit the economy and patients, and further evaluation of surveillance intervals tailored to individual risks is warranted.