Gastric Medullary Carcinoma Associated with Gastritis Cystica Profunda Exhibiting Dysplasia and Epstein-Barr Virus Expression

초록

Gastric medullary carcinomas consists of poorly differentiated polygonal tumor cells scattered throughout a prominent lymphoid stroma. The carcinoma cells contain Epstein-Barr virus(EBV) genetic sequences. EBV is a tumor related virus and has been reported to be associated with the development of gastric carcinoma. The pathogenetic role of EBV in gastric carcinomas still remains undefined. Gastritis cystica profunda is usually characterized by hyperplastic and cystic dilatation of pseudopyloric gland with submucosal invasion. Theses lesions may possess malignant histologic features as metaplastic and even dysplastic alteration, however they usually exhibit benign behavior. We report a case of gastric medullary carcinoma exhibiting positive EBER-in situ hybridization associated with gastritis cystica profunda which showed focal low grade dysplasia with EBER positivity. The patient was a 50-year-old male who had an incidentally found gastric carcinoma. His father and brother had suffered from gastric carcinoma. Resected stomach revealed two early cancers, type IIc+IIb at mid band lower body of posterior wall, measuring 3x2cm and 3x1.5cm, respectively. The tumors were confined within the submucosa without lymph node metastasis. Histologically they showed poorly differentiated carcinomas with extensive peritumoral lymphoplasmacytic infiltration. In addition, the mid and low body of posterior and anterior wall showed diffuse thickening of rugal folds, measuring 14x10cm. Cut surface revealed multiple small cysts containing mucus in the submucosa. Microscopic finding showed dilated cystic glands, some of which revealed nuclear stratification and mild atypia. EBER in situ hybridization revealed nuclear positivity in this dysplastic epithelium of gastritis cystica profunda as well as in the medullary carcinoma. This case suggests the pathogenetic role of EBV in medullary carcinoma during the early carcinogenesis.