Helicobacter pylori infection plays a crucial role not only in the pathogenesis but also in the treatment of low-grade gastric mucosa-associated lymphoid tissue (MALT) lymphoma. The aim of the present study was to evaluate whether H. pylori eradication provides a definite cure in the early stage of this neoplasia by means of a prolonged follow-up. All patients affected by low-grade gastric MALT lymphoma in stage IE that were referred to our department from January 1995 to June 1999 were enrolled in a prospective study. Diagnosis was histologically proved and H. pylori status was evaluated. Staging was performed according to a modified Ann Arbor classification. All patients who proved positive for H. pylori infection were treated with eradicating therapy, and a prolonged clinical and histologic follow-up was carried out. Until June 1999, seven low-grade gastric MALT lymphomas in stage IE were diagnosed (four men and three women; mean age, 56 years). All patients were H. pylori-positive and eradication was obtained in all of them after the first cycle of antibiotic therapy. Complete histologic regression of lymphoma was observed in all cases in a period variable between 3 and 6 months. The mean follow-up period was 42 months (range, 20-54). Only one patient showed a recurrence of lymphoma 22 months after treatment associated with H. pylori reinfection. Our results show the high efficacy of H. pylori eradication in determining a prolonged remission of low-grade gastric MALT lymphomas in stage IE. Thus, this therapeutic approach may avoid or delay the indication for more aggressive therapies, such as surgical resection.