A woman in her 40s underwent upper gastrointestinal endoscopy after an abnormality was detected during a physical examination. A 7-mm-sized, well-defined, faded, elevated lesion was observed in the greater curvature of the lower gastric body. This lesion was suspected to be an adenoma, and endoscopic submucosal dissection (ESD) was performed. Pathologically, the lesion was a tubular adenoma. The background mucosa had inverse atrophy, and the anti-gastric wall cell antibodies were more than 160 times higher than those of the previous case, along with elevated gastrin levels and low levels of vitamin B12. It is said that gastric mucosa with autoimmune gastritis has a high risk of developing gastric cancer or neoplastic lesions, and appropriate diagnosis and continuous follow-up are recommended.
