LISBON, Portugal--Recent evidence linking low-grade gastric lymphoma
with chronic Helicobacter pylori infection, which is said to trigger
antigenic stimulation and lymphoid cell invasion of the stomach
mucosa, has raised the provocative question of whether eradication
of H. pylori infection can cure gastric lymphoma.
Now Swiss and Italian investigators have confirmed anecdotal reports
that antibiotic treatment for H. pylori infection can accomplish
regression or disappearance of low-grade gastric lymphomas without
gastrectomy in as many as two thirds of patients with so-called
MALT (mucosa-associated lymphoid tissue) lymphomas.
Dr. Emanuele Zucca, of San Giovanni Hospital, Bellinzona (Switzerland),
said that, typically, a 2-week regimen of amoxicillin, 500 mg
tid, metronidazole, 400 mg tid, and bismuth, 120 mg qid, with
or without omeprazole, was prescribed for the 25 patients with
stage IE gastric MALT lymphoma who comprised the study population.
Antimicrobial therapy successfully eradicated infection in 96%
of patients and completely relieved symptoms of abdominal pain
and dyspepsia in 77%, Dr. Zucca reported at the congress of the
European Society of Medical Oncology. Most important, he stressed,
bimonthly gastroscopic examinations revealed lymphoma regression
in 15 (60%) of 25 patients, with one patient demonstrating wholly
normal histology and the remaining 14 showing only histologic
features of chronic gastritis.
"Lymphoma regression may take quite a long time," Dr.
Zucca cautioned. He pointed out that regression was documented
within 6 months of antibiotic therapy in eight of the 15 responding
patients but not until 9 to 12 months following treatment in the
seven other responders.
"Before concluding that antibiotic treatment can cure gastric
lymphoma, prolonged careful follow-up will be necessary because
of the long natural history of this disease," Dr. Zucca said.
"At present, however, an attempt to eradicate this infection
is mandatory before considering any other therapeutic options
in low-grade gastric lymphoma."
A randomized trial involving centers in Switzerland, Italy, and
Britain is being launched to investigate whether following antibiotic
treatment with chemotherapy provides any additional benefit.