A Case of Poorly Differentiated Adenocarcinoma Showing the Feature of a Submucosal Tumor

Abstract

A 59-year-old man was admitted to our hospital for further evaluation of the tumor of the stomach. Endoscopic and X-ray examination revealed the tumor showing submucosal-like with a small ulceration and irregular margin on the top. Initially, the pathological diagnosis of the biopsy specimen taken from the ulcer lesion was the suspicion of lymphoma. However, the second biopsy successfully disclosed the tumor as the poorly differentiated adenocarcinoma, and gastrectomy was performed.
Histological examination showed the tumor, measuring 20×16mm, was located in the submucosal layer almost covered by normal mucosa. Cells of poorly differentiated adenocarcinoma were scattered, and surrounded by abandoned lymphoid stroma. The diagnosis of epithelial origin tumor was established by Keratin stain of the tissue. Retrospectively, this case was considered to exhibit relatively typical sign of gastric carcinoma showing the feature of a submucosal tumor.