A case of fundic gland-type adenocarcinoma

Abstract

A 75-year-old man underwent upper gastrointestinal endoscopy for health screening. Endoscopic examination showed a lesion with the appearance of a submucosal tumor─an elevated area with a slightly depressed and erythematous portion─at the anterior wall of the lower body of the stomach. Histological analysis of biopsy specimens revealed the possibility of a gastric carcinoma. Endoscopic ultrasonography identified a hypoechoic mass which invaded deeply into the submucosal layer. However, histological findings from biopsy specimens taken at that time revealed normal gastric mucosa. ESD was performed for the purposes of diagnosis and treatment. Histopathological findings of the resected specimen revealed a well to moderately differentiated adenocarcinoma, and a regenerative epithelium distributed on the surface of the cancerous lesion. Immunohistochemical staining for the proton pump and Pepsinogen I was positive, suggesting a gastric adenocarcinoma of fundic gland type. Adenocarcinoma of fundic gland type was first reported by Ueyama and Yao in 2010, but endoscopic findings have not yet been established. Accumulation of characteristic endoscopic findings for this tumor is required to assist future diagnosis.