Natural Course of Atrophic Gastritis and Intestinal Metaplasia

Abstract

Atrophic gastritis (AG) and intestinal metaplasia (IM) are considered the main precursor lesions of gastric cancer, and the risk of gastric cancer in the gastric mucosa increases in the presence of AG and IM. The development of intestinal-type gastric adenocarcinoma represents the last step of an inflammation-metaplasia-dysplasia-carcinoma sequence, called the Correa cascade of multistep gastric carcinogenesis. The incidences of both AG and IM tend to increase with age. <i>Helicobacter pylori</i> is regarded the most important factor in the development of IM; the progression of AG to IM is also affected by numerous environmental factors and individual genetic factors. Therefore, understanding the natural course of AG and IM is very important, especially in areas with a high prevalence of gastric cancer such as Korea.