P1659 - Gastric Mucosal Associated Lymphoma without H. Pylori: A Case Highlighting the Need for Endoscopic Surveillance

Michelle D'Souza, MD, Amulya Penmetsa, MD
University of Rochester Medical Center, Rochester, NY

Introduction: While gastric Mucosal Associated Lymphoma (GML) is typically associated with Helicobacter pylori (HP), it can be develop when HP is absent. Gastric biopsies taken of the antrum and body to evaluate for HP can often be nonspecific, such as a plasma cell infiltrate. There are no guidelines to define when surveillance endoscopies should be performed in this scenario to evaluate for a progression into GML. We explore such a case within this report.

Case Description/Methods: A 66-year-old female with a history of anxiety and depression presented to the hospital with hematemesis and was found to have a gastric ulcer on esophagogastroduodenoscopy (EGD). Repeat EGD three months later showed gastric antral erythema with no residual ulcer. Gastric biopsies showed lymphoid infiltrate composed of roughly equal abundance of CD3+ T cells and CD20+/PAX5+ B cells with polytypic plasma cells primarily in the superficial aspect of the lamina propria. HP staining was negative. Molecular studies of IGH and IGK were weak negative. Repeat surveillance EGD three years later showed a 6mm linear gastric ulcer. On pathology, the areas previously noted as atypical lymphoid revealed extranodal marginal zone lymphoma of the gastric body (lesser curvature), the ulcer in the body, and in the fundus. Remainder of biopsies throughout the stomach were normal and HP was negative. Stool testing confirmed negative HP status. She underwent PET/CT with no hypermetabolic activity in the stomach or elsewhere, and received radiation treatment.

Discussion: While GML associated with HP often regresses with complete treatment of HP, GML without HP is very rare and irradiation of the stomach is typically the treatment of choice. Several studies have demonstrated an excellent response rate (95%) of GML treated with radiation therapy, and a very low risk of local relapse (< 10%) with a good tolerance for treatment and minimal long-term side effects. Usually, GML is a multifocal disease, and the entire stomach should be considered to harbor disease even when it appears confined to one area. In our patient, initial EGD showed a polytypic plasma cell infiltrate and an arbitrary decision was made to repeat EGD three years afterwards for surveillance. There is a paucity of data regarding the time course and likelihood of progression of precursor plasma cells into GML, and it is therefore difficult to determine the ideal endoscopic surveillance interval. Further studies need to be pursued to better guide surveillance and treatment.


Disclosures:


Michelle D'Souza, MD, Amulya Penmetsa, MD. P1659 - Gastric Mucosal Associated Lymphoma without <i>H. Pylori</i>: A Case Highlighting the Need for Endoscopic Surveillance, ACG 2024 Annual Scientific Meeting Abstracts. Philadelphia, PA: American College of Gastroenterology.