A CASE OF HELICOBACTER. PYLORI-NEGATIVE DIFFERENTIATED-TYPE GASTRIC CARCINOMA WITH A GASTRIC MUCIN PHENOTYPE TREATED BY ESD

Abstract

A 50-year-old woman was referred to our hospital for a depressed lesion on the anterior greater curvature of the middle body of the stomach that had been identified by screening endoscopy. The pathology of biopsy specimens obtained from the lesion demonstrated adenoma. However, we diagnosed the lesion as a well differentiated adenocarcinoma confined within the mucosal layer using EUS and magnifying endoscopy with narrow band imaging. The lesion was excised by ESD in December 2009. Histopathology of the resected specimen revealed a well differentiated adenocarcinoma within the mucosal layer [0-IIc, UL(-), ly0, v0]. The tumor's phenotype was classified as the gastric type. Helicobacter pylori (H. pylori) infection was not identified by the histological examination, blood antibody test or the urea breath test even though there was no history of H. pylori eradication therapy. We therefore considered that the patient had not been infected with H. pylori. This paper reports on a rare case of a well differentiated adenocarcinoma with a gastric type phenotype without H. pylori infection treated by ESD.