To investigate the prevalence of H. pylori infection in patients with early stage of primary low-grade B cell lymphoma of MALT of the stomach in Taiwan.~-To evaluate the therapeutic effectiveness of H. pylori eradication in stage IE & IIE-1 primary low-grade B cell lymphoma of MALT of the stomach.~To evaluate the efficacy of Helicobacter pylori eradication therapy with respect to objective regression rate and time to disease progression of primary low-grade gastric MALToma.~To estimate any differences in therapeutic efficacy related to different stage of disease,eg. stage IE v.s. stage IIE-1.~To identify the causes of treatment failure, such as the stage of tumor, the presence of large cell component, and/or persistent, reactivation or reinfection of H. pylori etc.
To evaluate the therapeutic effectiveness of H. pylori eradication in stage IE & IIE-1 primary low-grade B cell lymphoma of MALT of the stomach