Early treatment of stomach bug may cut cancer risk
NEW YORK (Reuters Health) - Experiments in mice show that promptly treating a stomach infection that can trigger cancer seems to reduce the likelihood of that happening.
Stomach infection with a bug called Helicobacter pylori is common in humans. It's known to cause stomach ulcers, and in some people it can eventually lead to gastric cancer.
Dr. Chung-Wei Lee of the Massachusetts Institute of Technology in Cambridge and colleagues found that mice with H. pylori infection left untreated developed pre-cancerous changes in the stomach lining after 28 weeks from the initial infection.
The researchers then looked at the effect of treating H. Pylori infections, using the same medications used to eradicate the infection in humans -- a combination of gastric acid suppressors and antibiotics.
After infection, mice were treated 8, 12 or 22 weeks later. H. pylori eradication at 8 weeks post-infection completely prevented the development of precancerous changes, Lee and colleagues report in the journal Cancer Research. The effects of later treatment were less striking.
The investigators acknowledge that most clinical trials in patients have not noted an overall reduction in pre-cancerous lesions or actual gastric cancer in patients receiving H. pylori eradication therapy.
However, they researchers point out that precancerous lesions resolve over time if the patient remains free of H. pylori. "This suggests that significant improvement of gastric lesions and reduction of gastric cancer prevalence may not be observed during the first few years after treatment."
They conclude that larger clinical trials with human patients and a long follow-up period are warranted.
SOURCE: Cancer Research, May 1, 2008.