Antibiotic Therapy and Antacids in Patients With Malt Lymphoma of the Stomach

OBJECTIVES: I. Evaluate the response of gastric lymphoma of mucosa-associated lymphoid tissue
(MALT) to treatment for Helicobacter pylori infection with antibiotics (amoxicillin,
clarithromycin, tetracycline, and metronidazole) and with gastric acid inhibitors (omeprazole
and bismuth subsalicylate). II. Correlate response with endoscopic tumor grade and clinical
and pathological parameters. III. Assess the incidence of H. pylori infection in patients
with gastric MALT lymphoma.

OUTLINE: All patients are treated on Regimen A; those receiving tetracycline on Regimen A are
switched to Regimen B for their second course; those receiving amoxicillin for their first
course receive tetracycline for their second course. Regimen A: Antibiotic Therapy with
Gastric Acid Inhibition. Amoxicillin (or Tetracycline in penicillin-allergic patients);
Clarithromycin; with Bismuth Subsalicylate; Omeprazole. Regimen B: Antibiotic Therapy with
Gastric Acid Inhibition. Tetracycline; Metronidazole, METRO, NSC-50364; with Bismuth
Subsalicylate; Omeprazole.

PROJECTED ACCRUAL: 75 patients will be entered over 3 years.

DISEASE CHARACTERISTICS: Suspected gastric lymphoma or documented gastric lymphoma of
mucosa-associated lymphoid tissue (MALT) that is stage IE Gastric MALT lymphoma with
perigastric lymph nodes identified on endoscopic ultrasound eligible at MDACC and Houston
VA Medical Center only No indication for expeditious treatment with chemotherapy,
radiotherapy, or surgery based on clinical condition, underlying illness, or tumor stage

PATIENT CHARACTERISTICS: Age: 18 to 80 Performance status: Not specified Hematopoietic: Not
specified Hepatic: Not specified Renal: Not specified Other: No contraindication to
endoscopy or biopsy No pregnant or nursing women Adequate contraception required of fertile
patients

PRIOR CONCURRENT THERAPY: No concurrent chemotherapy or radiotherapy