The value of EUS in predicting the response of gastric mucosa-associated lymphoid tissue lymphoma to Helicobacter pylori eradication

Background: Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is associated with Helicobacter pylori infection, and regression of the tumor has been described after its eradication. Objective: To determine the value of EUS, in addition to other clinical/endoscopic features, in predicting the response of low-grade MALT lymphoma to H pylori eradication. Design: A retrospective, single-center study. S etting and Patients: Twenty-two patients with primary gastric MALT lymphoma were identified through a retrospective review of charts of patients seen at the American University of Beirut Medical Center. Only 19 patients with histopathologically confirmed gastric MALT lymphoma and H pylori infection who had EUS staging were included in the study. Main Outcome Measurements: Regression of the gastric MALT lymphoma as determined by follow-up endoscopy and mucosal biopsies. Results: Patients with disease restricted to the gastric mucosa had a significantly higher rate of complete remission after H pylori eradication compared with patients who had disease infiltrating into the gastric submucosa (77.8% vs 12.5%, P value .007). There was no statistical difference in terms of the mean follow-up time to achieve such response (P value .212). Age, sex, location of the tumor within the stomach, and endoscopic appearance did not correlate with the probability of complete remission of the MALT lymphoma. Limitations: The limitations include a retrospective design and a relatively small sample population. Conclusion: EUS determination of the invasion depth of gastric MALT lymphoma helps predict a complete response to H pylori eradication.