3229 Helicobacter pylori-Negative Gastric Mucosa-Associated Lymphoid Tissue Lymphomas: A Challenge in Treatment Options

Abstract

INTRODUCTION: Primary gastric lymphoma is a rare entity of which the specific variant, mucosa-associated lymphoid tissue (MALT) lymphomas may be the best recognized given its association with Helicobacter pylori (H. pylori) infection. It has been thought that repetitive immune stimulation from underlying infection is influential in the pathogenesis of this tumor. However up to 10% of gastric MALT lymphomas are diagnosed without a concomitant H. pylori infection. The pathogenesis and management of H. pylori-negative gastric MALT lymphomas remains uncertain. CASE DESCRIPTION/METHODS: 65 year old woman with Celiac disease and GERD presented with worsening severe reflux and epigastric pain. She underwent EGD which revealed multiple superficial ulcers in the cardia with notable nodularity, ulceration, and friability. Cold forceps biopsies of the abnormal mucosa demonstrated diffuse atypical small B-Cell lymphoid infiltrate with features compatible with low grade MALT lymphoma. Of note, immunostain for H. Pylori was negative. Subsequent H. pylori stool antigen assay as well H. pylori IgG, IgM, and IgA were all negative. Given her negative antibodies indicating she truly had no exposure to H. Pylori, the patient has been referred to oncology for multidisciplinary management. DISCUSSION: This case of early stage gastric MALT lymphoma without evidence of active H. pylori infection elucidates that there is limited literature for the management for these patients. Studies have suggested that H. pylori eradication therapy can be efficacious for a proportion of H. pylori-negative gastric MALT lymphomas, possibly due to a false negative detection by biopsy. Local radiation therapy with curative intent and single agent rituximab therapy rather than H. pylori eradication have also been explored as alternate options. The data stems from retrospective studies and single agent prospective trials. Thus, there may be a role for future research directly comparing treatment strategies for optimal management of this clinical entity.