Amoxicillin plus omeprazole appears to slow the progression of histologic abnormalities, but a reduced incidence of gastric cancer remains unproved.
Epidemiologic evidence strongly suggests a link between gastric cancer and Helicobacter pylori (HP) infection. In a randomized trial performed in China (but supported by the U.S. National Cancer Institute), researchers examined the effect of several interventions — including HP eradication — on the prevalence of precancerous gastric lesions.
The study included 3365 subjects (age range, 35–64), 67% of whom had HP-positive serology. On baseline endoscopic biopsies, nearly all patients had gastric histologic abnormalities, ranging from superficial gastritis to severe dysplasia. In a 2 x 2 x 2 factorial design, each HP-positive patient was randomized to HP eradication therapy (amoxicillin plus omeprazole for 2 weeks) or placebo, a daily garlic capsule or placebo, and a daily supplement (containing vitamin C, vitamin E, and selenium) or placebo. HP-negative patients participated only in the garlic and vitamin arms of the study.
After 7 years, HP eradication resulted in significantly less progression of histologic abnormalities than did placebo. In particular, compared with the placebo group, the HP-eradication group shifted away from deep intestinal metaplasia and toward mild or moderate (as opposed to severe) chronic atrophic gastritis. Although fewer gastric cancers were diagnosed in the HP-eradication group than in the placebo group (19 vs. 27 cases among about 1130 subjects in each group), the difference was not statistically significant. No favorable outcomes with garlic or vitamin therapy were noted.
Comment: This study suggests that H. pylori eradication therapy retards the progression of precancerous gastric lesions, at least among this Chinese population; however, a reduced incidence of gastric cancer remains to be proved. The authors note that follow-up — including annual endoscopies for patients with dysplasia — is continuing.
— Allan S. Brett, MD
Citation(s):
You W-C et al. Randomized double-blind factorial trial of three treatments to reduce the prevalence of precancerous gastric lesions. J Natl Cancer Inst 2006 Jul 19; 98:974-83.