BACKGROUNDThe goals of the current study were to elucidate the long‐term outcome of Helicobacter pylori eradication therapy for gastric mucosa‐associated lymphoid tissue (MALT) lymphoma and to clarify the therapeutic efficacy of stomach‐conserving treatments for patients not responding to eradication therapy.METHODSNinety‐six patients with gastric MALT lymphoma, including 17 patients with areas of diffuse large B‐cell lymphoma, were treated by H. pylori eradication. Patients not responding to eradication therapy underwent either a gastrectomy, multiagent chemotherapy, oral monochemotherapy (OMC), or radiotherapy (RT). Predictive factors for the response to eradication therapy, overall survival (OS), and event‐free survival (EFS) were determined by the Kaplan–Meier analysis with the log‐rank test. The efficacy of second‐line treatment was compared between OMC and RT.RESULTSAfter eradication therapy, 62 (65%) patients achieved complete disease remission (CR). Transient histologic disease recurrence was confirmed in 4 (6.5%) of 62 patients with CR during the follow‐up (median, 37.5 months). The OS and EFS probabilities after 5 years were 0.96 and 0.80, respectively. Second‐line treatment was performed in 31 patients; gastrectomy in 4 patients, multiagent chemotherapy in 5 patients, OMC in 12 patients, and RT in 10 patients. There were no differences in the CR rate, OS, EFS, or toxicity between the OMC and RT groups.CONCLUSIONSH. pylori eradication therapy was an effective first‐line treatment for patients with gastric MALT lymphoma, which led to a favorable long‐term outcome. OMC and RT had an equivalent efficacy as a second‐line treatment in nonresponding patients to eradication therapy. Cancer 2005. © 2005 American Cancer Society.