抄録
Gastric hyperplastic polyps are associated with atrophic gastritis caused by Helicobacter pylori (H. pylori) infection and possess a low but notable malignant potential. In the absence of malignant transformation, H. pylori eradication therapy is typically performed, often resulting in regression or disappearance of the polyps. However, in some cases, polyps may enlarge or undergo morphological changes despite successful eradication. The "scarf-ring sign" is a rare endoscopic finding in which a gastric polyp prolapses into the duodenum, with its stalk passing through the pyloric ring. When accompanied by symptoms such as abdominal pain, nausea, or vomiting due to obstruction, it is diagnosed as ball valve syndrome.
We report the case of a 57-year-old man who was found to have atrophic gastritis and a 5-mm Yamada type II hyperplastic polyp in the pyloric region during a health checkup six and a half years ago. As his serum anti-H. pylori IgG antibody was positive, he underwent successful eradication therapy after a second-line regimen. At follow-up endoscopy one and a half years later, the polyp had enlarged to 10 mm and changed to a pedunculated Yamada type IV polyp. Subsequently, the scarf-ring sign and further enlargement were observed, although no obstructive symptoms developed. The patient remains under endoscopic surveillance while treatment options are being considered.
