Cleveland Clinic Journal of MedicineGastric Intestinal Metaplasia and Gastric Cancer Prevention: Watchful Waiting

Gastric Intestinal Metaplasia: A Window into Gastric Cancer Progression and the Impact of Environmental and Genetic Factors

Gastric intestinal metaplasia (GIM) represents a pivotal stage in the progression towards gastric cancer, highlighting the intricate interplay between environmental influences, such as Helicobacter pylori infection, and genetic predisposition. This comprehensive review delves into the multifaceted nature of GIM, encompassing its classification, risk factors, histological types, and the implications for clinical management. With a focus on the Correa cascade and the differentiation between complete and incomplete GIM, the article offers valuable insights into the pathways leading to malignancy and the importance of targeted surveillance and management strategies in high-risk populations.

Key Points

1. GIM and Gastric Cancer Risk: GIM, often a response to gastric injury, can progress to gastric cancer, especially in cases of ongoing injury without treatment.
2. Histologic Types of GIM: Two types are identified – complete GIM with intestinal mucin markers, and incomplete GIM with both gastric and intestinal mucin markers, the latter associated with higher cancer risk.
3. Correa Cascade: Describes the progression from nonatrophic gastritis to multifocal atrophic gastritis, then to GIM, and ultimately to adenocarcinoma.
4. Environmental Metaplastic Atrophic Gastritis (EMAG): Predominantly caused by H. pylori infection, it’s a leading cause of chronic gastritis, and uneradicated infection can progress to atrophic gastritis.
5. Autoimmune Metaplastic Atrophic Gastritis (AMAG): A less common but significant cause of chronic gastritis, often presenting with vitamin B12 deficiency or iron-deficiency anemia.
6. Risk Stratification: Identifying high-risk patients through clinical, endoscopic, and histologic features is crucial for targeted endoscopic surveillance.
7. Endoscopic Management: Varies geographically; high-risk patients are recommended regular surveillance, with guidelines differing between Eastern and Western regions.
8. Nonendoscopic Management: Includes risk-factor modification and H. pylori eradication to prevent progression to gastric cancer.
9. Global Guideline Variations: There are significant differences in the management of GIM globally, reflecting varying incidences of gastric cancer.
10. Epidemiological Considerations: The incidence of gastric cancer and GIM varies geographically and is influenced by environmental and genetic factors.

According to the World Cancer Research Fund, stomach cancer is the fifth most commonly occurring cancer in men and the seventh in women, with nearly 1.09 million new cases in 2020 globally.

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