Long-term monitoring of gastric atrophy and intestinal metaplasia after Helicobacter pylori eradication.

Improvements of atrophy and intestinal metaplasia which is seen after H. pylori eradication may be regarded as an important factor of gastric cancer prevention. Although many studies reported the alteration of gastric mucosa after H. pylori eradication, most of the results do not agree. Recently, two meta-analyses showed significant improvement of atrophy (one study showed improvement in both corpus and antrum, and the other showed improvement in corpus but not in antrum), whereas improvement of intestinal metaplasia was not shown in either corpus or antrum. However, one reason why conclusions are different is considered to be that the observation period after eradication was short, and another reason is considered to be that almost studies examined only two points in gastric mucosa for histological analysis. Further examination with a greater number of subjects and with longer follow up period should be required to clarify the mechanism of gastric injury and improvement of gastric mucosa, especially atrophy and intestinal metaplasia after H. pylori eradication.