Woman in her fifties. She had been received regularly an upper gastrointestinal endoscopy noted for gastric polyp for several years. Biopsy sample from the polyp was suspected malignancy, so she was referred to come our hospital for examination. Blood examination revealed anti-parietal cell antibody positive, hypergastrinemia and anti-Helicobacter pylori antibody negative. She had severe atrophic gastritis in the body and fundus, but no atrophic gastritis in the antrum. Based on the above, we diagnosed autoimmune gastritis (AIG). We also detected hyperplastic type polyp in anterior wall in the middle body. Magnify endoscopy revealed hyperplastic change and abnormal vessel in the polyp. Afterward we conducted endoscopic mucosal resection (EMR) for the polyp, which was pathologically diagnosed as well-differentiated adenocarcinoma was diagnosed pathologically from EMR sample. It was reported that the risk of cancer in hyperplastic type polyp in AIG was high. We will have to check H. pylori infection but also AIG about gastric hyperplastic type polyp with atrophic gastritis.
