Diagnosis of a Gastric Mucosa-associated Lymphoid Tissue Lymphoma by Endoscopic Ultrasonography-guided Biopsies in a Patient with a Parotid Gland Localization

We report the case of a 32-year-old man with a low-grade mucosa-associated lymphoid tissue (MALT) lymphoma of the parotid gland associated with Sjogren syndrome. He underwent an upper endoscopy as part of the screening of a gastric localization which showed a diffuse non-specific gastritis. However, endoscopic ultrasonography (EUS) evidenced a focal wall thickening of the vertical portion of the smaller curvature. EUS-guided biopsies of this area disclosed a MALT lymphoma, whereas biopsies under endoscopy concluded to mild chronic gastritis. The search for Helicobacter pylori infection remained negative. Four months after treatment with anti-CD20 antibodies, EUS showed a diminution of the abnormal thickening of the second layer. Regression was confirmed histologically on new EUS-guided biopsies. MALT lymphoma is usually considered a localized disease; however, dissemination is probably more frequent than initially believed. Our case reflects the importance of a systematic screening for a gastric localizat...