Mucosa-associated lymphoid tissue (MALT) lymphoma of the esophagus

A 70-year-old man was referred for dysphagia.Esophagogastroduodenoscopy (EGD) revealed a submucosal tumor (SMT) covered with smooth normal mucosa in the upper thoracic esophagus (Fig. 1a).The lesion had a longitudinal concave elevation and circumscribed about half around.Endoscopic ultrasonography showed an isoechoic homogeneous mass located in the second to third layer (Fig. 2).Computed tomography (CT) showed 5-cm esophageal wall thickness in the lesion along and swelled multiple mediastinal lymph nodes.The biopsy tissue showed aggregation of small lymphocytes in subepithelial area (Fig. 3), which were immunohistochemically positive for CD20 and negative for CD10, CD23, and cyclin D1.Rearrangement of immunoglobulin heavy-chain joining region genes was found.Based on those findings, we diagnosed extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) type of the esophagus.After eradication of Helicobacter pylori, he was treated with rituximab (375 mg/m 2 ).