Endoscopic Ultrasonographic Features of Gastric Mucosa-Associated Lymphoid Tissue Lymphoma with a ‘Pseudocircumvolutory’ Appearance

1Department of Gastroenterology, Faculty of Medicine, Centro Hospitalar S. Joao; 2Department of Biochemistry, Faculty of Medicine, University of Porto; 3Deparment of Hematology, Centro Hospitalar S. Joao, Porto, Portugal Correspondence: Dr Joao Santos-Antunes, Gastroenterology Department, Centro Hospitalar S. Joao. Al. Prof. Hernâni Monteiro 4200–319 Porto, Portugal. Telephone 351-22-551-2100, fax 351-22-502-5766, e-mail joao.claudio.antunes@gmail.com Received for publication July 11, 2013. Accepted September 15, 2013 Case presentation A 45-year-old man with a history of drug abuse, alcoholism and heavy smoking habits was referred to the hepatology outpatient clinic because of the presence of anti-hepatis B virus (HBV) surface antigen, anti-HBV core antigen and anti-hepatitis C virus antibodies. He was being treated with tiapride and methadone. He had no anemia, a normal white blood cell count, negative autoimmune serology, undetectable HBV DNA and hepatitis C virus RNA, and mildly elevated aminotransferase levels. Immunoglobulin (Ig) M and IgA levels were elevated, with a monoclonal peak in protein electrophoresis. Myelography and bone biopsy revealed a cytological phenotype of Waldestrom macroglobulinemia with bone marrow involvement of small B cell lymphocytes, compatible with lymphoplasmacytoid lymphoma. An abdominal ultrasound and computed tomography scan revealed a thick gastric wall, and retroperitoneal and mesenteric adenopathies, raising suspicion for malignancy. Esophagogastroduodenoscopy was remarkable for diffuse hard and edematous gastric folds of the body and fundus with some erosions (Figure 1). Endoscopic ultrasonography showed an asymmetrically thickened gastric wall (20 mm maximum), with disease limited to the mucosa and preservation of wall layers, and adenopathies (Figures 2 to 4). Biopsies were performed and histology revealed dense infiltration of mucosa by small B cells with irregular nuclei, plasmacytic differentiation and formation of lymphoepithelial lesions, strongly suggestive of mucosa-associated lymphoid tissue (MALT) lymphoma. imagEs of thE month