Common Locations of Gastric Cancer: Review of Research from the Endoscopic Submucosal Dissection Era

Detection of early-stage gastric cancer improves the prognosis of patients. Endoscopic submucosal dissection (ESD) is a curative and stomach-preserving treatment for early gastric cancer (EGC) associated with a low risk of lymph node metastasis. However, several studies have reported missed diagnosis of gastric cancer. Therefore, endoscopists are required to learn accurate diagnostic skills to eliminate endoscopic blind spots. A systematic screening protocol to map the entire stomach without blind spots reduces the risk of missed lesions. Knowledge of the features of EGC or dysplasia is essential to identify suspicious lesion. Information of the common sites of occurrence of EGC can also enable a detailed endoscopic examination to improve detection rates. Previous reports investigating the location of gastric cancers resected by ESD or surgery showed that the antrum and lesser curvature of stomach were predominantly affected. Helicobacter pylori-induced atrophic changes advance from the antrum to the corpus along the lesser curvature, predominantly affecting these areas. Gastric cancers in the antrum and the lower corpus are also commonly missed during screening examination. Therefore, a careful examination of the lower third stomach is warranted to avoid missing synchronous and metachronous gastric lesions. Knowledge of the location of EGC enables accurate endoscopic examination and detection of EGC in early stage.