Antibiotic Regimen Leads to Lymphoma Regression

LISBON, Portugal--Recent evidence linking low-grade gastric lymphomawith chronic Helicobacter pylori infection, which is said to triggerantigenic stimulation and lymphoid cell invasion of the stomachmucosa, has raised the provocative question of whether eradicationof H. pylori infection can cure gastric lymphoma.

Now Swiss and Italian investigators have confirmed anecdotal reportsthat antibiotic treatment for H. pylori infection can accomplishregression or disappearance of low-grade gastric lymphomas withoutgastrectomy in as many as two thirds of patients with so-calledMALT (mucosa-associated lymphoid tissue) lymphomas.

Dr. Emanuele Zucca, of San Giovanni Hospital, Bellinzona (Switzerland),said that, typically, a 2-week regimen of amoxicillin, 500 mgtid, metronidazole, 400 mg tid, and bismuth, 120 mg qid, withor without omeprazole, was prescribed for the 25 patients withstage IE gastric MALT lymphoma who comprised the study population.

Antimicrobial therapy successfully eradicated infection in 96%of patients and completely relieved symptoms of abdominal painand dyspepsia in 77%, Dr. Zucca reported at the congress of theEuropean Society of Medical Oncology. Most important, he stressed,bimonthly gastroscopic examinations revealed lymphoma regressionin 15 (60%) of 25 patients, with one patient demonstrating whollynormal histology and the remaining 14 showing only histologicfeatures of chronic gastritis.

"Lymphoma regression may take quite a long time," Dr.Zucca cautioned. He pointed out that regression was documentedwithin 6 months of antibiotic therapy in eight of the 15 respondingpatients but not until 9 to 12 months following treatment in theseven other responders.

"Before concluding that antibiotic treatment can cure gastriclymphoma, prolonged careful follow-up will be necessary becauseof the long natural history of this disease," Dr. Zucca said."At present, however, an attempt to eradicate this infectionis mandatory before considering any other therapeutic optionsin low-grade gastric lymphoma."

A randomized trial involving centers in Switzerland, Italy, andBritain is being launched to investigate whether following antibiotictreatment with chemotherapy provides any additional benefit.