Effects of Helicobacter pylori Eradication on Early Stage Gastric Mucosa-Associated Lymphoid Tissue Lymphoma

BACKGROUND & AIMS: Different remission rates of gastric low-grade, B-cell, mucosa-associated lymphoid tissue (MALT) lymphoma have been reported after Helicobacter pylon eradication. We assessed the long-term remission and relapse rates of early stage MALT lymphoma in patients treated only by H pylori eradication and identified factors that might predict outcome. METHODS: This systematic review analyzed data from 32 studies, including 1408 patients. RESULTS: The MALT lymphoma remission rate was 77.5% (95% confidence interval, 75.3-79.7), and was significantly higher in patients with stage I than stage II1 lymphoma (78.4% vs 55.6%; P = .0003) and in Asian than in Western groups (84.1% vs 73.8%; P = .0001). Neoplasia confined to the submucosa regressed more frequently than that with deeper invasion (82.2% vs 54.5%; P = .0001); patients with lymphoma localized to the distal stomach experienced regression more frequently than those with lymphoma of the proximal stomach (91.8% vs 75.7%; P = .0037). The remission rare was higher among patients without the API2-MALT1 translocation than in those with this translocation (78% vs 22.2%; P = .0001). In an analysis of data from 994 patients, 7.2% experienced lymphoma relapse during 3253 patient-years of follow-up evaluation, with a yearly recurrence rate of 2.2%. Infection and lymphoma were cured by additional eradication therapy in all patients with H. pylori recurrence (16.7%). Five (0.05%) of:the patients initially cured of lymphoma developed high-grade lymphoma within 6 to 25 months of therapy. CONCLUSIONS: H pylori eradication is effective in treating approximately 75% of patients with early stage gastric lymphoma. Long-term follow-up evaluation of these patients is needed to detect early lymphoma relapse or progression.