A Case of Early Gastric Cancer Manifesting as a Submucosal Tumor

Abstract

Abstract: Gastric cancer manifesting as a submucosal tumor (SMT) is not common. A gastric barium meal and endoscopic studies performed on a 49‐year‐old male with epigastric pain, revealed an elevated lesion with bridging folds and central depression on the posterior wall of the lower body. An endoscopic ultrasonography (EUS) revealed a hypoechoic mass lesion within the submucosal layer. Due to an increase in the size of the tumor and its central depression during the subsequent year and a half, the patient was admitted for closer examination. Endoscopic biopsy material from the deeper layer, obtained by mucosal resection, revealed a poorly differentiated adenocarcinoma. Microscopic examination of the resected stomach showed a poorly differentiated adenocarcinoma within the submucosal layer, with considerable lymphocyte infiltration. Immunohistological examination disclosed marked T cell infiltration adjacent to the cancer cells. We suggest that considerable lymphocyte infiltration, particularly T cells, may have some role in the protective reaction against cancer cells. Our case was diagnosed as being cancer 18 months after the first endoscopic study. The biopsy material taken from the depression at the time of the first examination showed benign findings and a EUS revealed typical SMT. In the case of SMT shown by EUS to be a hypoechoic mass lesion in the submucosal layer, it is recommended that biopsy material be obtained from the deeper layer using methods available such as artificial ulcer formation.