QUALITATIVE DIAGNOSIS OF INTESTINAL-TYPE DIFFERENTIATED GASTRIC CANCER THAT ORIGINATED IN HELICOBACTER PYLORI-UNINFECTED MUCOSA BASED ON FINDINGS OF A LIGHT BLUE CREST AND WHITE OPAQUE SUBSTANCE: A CASE REPORT

Abstract

A 34-year-old man underwent endoscopic evaluation, which revealed an elevated lesion (10 mm) with an erosion-like depression at the antrum; however, qualitative diagnosis could not be established. Re-evaluation was performed after administration of an antacid. Magnifying endoscopy with narrow-band imaging confirmed an irregular microvascular and microsurface pattern within a clear tumor demarcation line. A partial light blue crest and an irregular white opaque substance were visualized, and the lesion was diagnosed as differentiated early gastric cancer with an intestinal phenotype. We performed endoscopic submucosal dissection for tumor resection. Endoscopic and histopathological evaluation revealed no atrophy or intestinal metaplasia of the background mucosa. Serum Helicobacter pylori antibody and fecal antigen tests showed negative results. The final histopathological diagnosis was a well-differentiated adenocarcinoma with an intestinal phenotype that originated in H. pylori-uninfected mucosa.