Prospective Study of First-line Antibiotic Therapy for Early-stage Gastric MALT Lymphoma for Treatment Outcome

Inclusion Criteria: * The patients must have histologically confirmed primary gastric MALT lymphoma with or without clustering large cells (extranodal marginal zone lymphoma, and diffuse large cell lymphoma with features of MALT by REAL/WHO classification, Harris NL et al. 1994). * 1.1 The diagnosis of primary gastric lymphoma must fulfill the criteria of Dawson \[38\]. * (1)No enlargement of peripheral or mediastinal lymph node; * (2)Peripheral blood smear revealing no leukemic or lymphomatous abnormalities; * (3)Predominant of alimentary tract lesions with any adenopathy corresponding to accepted lymphatic drainage route; and * (4)No involvement of liver or spleen except by extension of contiguous disease. * 1.2 The diagnosis of MALT lymphoma will be made by histopathologists from individual hospitals, in accordance with criteria defined by Isaacson et al. and Chang et al, and will be reviewed by the members of the TCOG Pathology Committee. This pathology review mechanism had been functioned well in the previous T1296 study (see J Natl Cancer Inst. 2005;97:1345-53) * 1.3 The patient must have no prior chemotherapy or radiotherapy for his/her gastric lg- or hg-MALToma. * Patients must have evaluable disease by endoscopy and/or the nodal status by computed tomography. Endoscopic ultrasonography (EUS) is mandatory to evaluate the depth of tumor infiltration and for status of perigastric lymph node enlargement. * Patients must have documented H. pylori …