Gastrointestinal: Gastric mucosa‐associated lymphoma presented with unique vascular features on magnified endoscopy combined with narrow‐band imaging

Abstract

Gastric lymphoma arising from mucosal associated lymphoid tissue (MALT) has distinct clinical and histological characteristics compared with nodal B-cell lymphoma. Magnified endoscopy (ME) combined with narrow band imaging (NBI) is widely used and the usefulness is well recognized for the diagnosis of gastritis and gastric cancer. However, there has been no report on ME combined with NBI for gastric MALT lymphoma, despite the necessity of differentiating it from gastric cancer. We report a case ofgastricMALTlymphomainwhichMEcombinedwithNBIcould detectuniquevascularfeaturesdifferentfromthoseseenincircumscribed atrophic gastritis or poorly differentiated adenocarcinoma. A 66-year-old woman underwent endoscopic screening of the upper gastrointestinal tract revealed ill-defined, brownish, superficial depressed lesion in the anterior wall of the upper gastric body (Fig. 1). ME combined with NBI system, consisting of an image processor (CV-260SL, Olympus Medical Systems, Tokyo, Japan), a light source (CLV-260SL), and a zoom endoscope (GIF-Q240Z) showed the disappearance of the surface structure and the appearance of abnormal blood vessels.Abnormal vessels were defined as new vessels that were not seen in the adjacent mucosa. They were large vessels like a tree trunk with long, bare branches that can be called as ‘tree like appearance’ (Fig. 2). Biopsy was taken from this abnormal portion and revealed hyperplasia of atypical centrocyte-like cells with small to medium-sized, ovoid nuclei and clear cytoplasm in the lamina propria mucosae and their infiltration among glandular epithelial cells, suggesting lymphoepithelial lesion. The atypical lymphocytes were immunohistochemically CD20+ ,C D10-, and CD5-. These findings were consistent with gastric MALT lymphoma. In this case report, we have shown that the tree-like appearance of the abnormal blood vessels, clearly observed by ME with NBI, could be one of the unique features suggestive of gastric MALT lymphoma. This finding could be helpful because superficial depressed type lesion potentially include circumscribed atrophic gastritis and poorly differentiated adenocarcinoma. Of note, these vascular findings are relatively easy to detect by using NBI, because NBI can present clearly defined vascular image. Therefore, our data also suggest the importance of NBI for the endoscopic evaluation of gastric MALTlymphoma.The combination of ME with NBI may also reduce the number of biopsy of gastric MALT lymphoma because it can provide precise information about the distribution of MALT lymphoma in the stomach.