Most Common Risk Factors for Gastric Malignancy
The most common risk factors for gastric cancer include chronic Helicobacter pylori infection, immigration from high-incidence regions, family history of gastric cancer in first-degree relatives, non-White racial/ethnic background, tobacco smoking, high-salt diet, and living in persistent poverty. 1
Primary Risk Factors
Infectious and Inflammatory
- Chronic H. pylori infection remains the most significant modifiable risk factor, particularly for non-cardia gastric adenocarcinoma 1
- Epstein-Barr virus infection increases risk 2
- Autoimmune gastritis with pernicious anaemia (annual incidence 0.27%) 3
Demographic and Geographic Factors
- First-generation immigrants from moderate-to-high incidence regions (Eastern Europe, Andean Latin America, East Asia) where gastric cancer incidence is ≥10-12 per 100,000 people 1
- Non-White racial and ethnic groups with established moderate-to-high gastric cancer incidence 1
- Age ≥45 years (screening initiation age) 1
- Male sex 3
Family History and Genetic Syndromes
- First-degree relative with gastric cancer (screening should start 10 years earlier than the youngest affected relative) 1
- Hereditary GI polyposis syndromes: familial adenomatous polyposis, Peutz-Jeghers syndrome, juvenile polyposis, MUTYH-associated polyposis, gastric adenocarcinoma and proximal polyposis of the stomach 1
- Hereditary cancer syndromes: Lynch syndrome, hereditary breast and ovarian cancer syndrome, Li-Fraumeni syndrome 1
Lifestyle and Dietary Factors
- Tobacco smoking (>20 pack-years significantly increases risk) 1, 4
- High-salt diet and processed meats 1, 4
- Red meat consumption 2
- Chronic consumption of processed foods 1
- Excessive alcohol intake 4
Socioeconomic Factors
- Living in persistent poverty (defined as locations where ≥20% of residents have lived below federal poverty level for 4 decades) - gastric cancer mortality rates are 43% higher in these US counties compared to non-poverty counties 1
- Limited access to quality healthcare 1
Premalignant Conditions
- Gastric intestinal metaplasia (GIM) 1
- Chronic atrophic gastritis 2
- Gastric adenomas and hyperplastic polyps 3
Other Medical Conditions
Important Clinical Considerations
The 2025 AGA guidelines emphasize that gastric cancer risk assessment must be individualized and personalized rather than using simple age-based universal screening like colorectal cancer, as this would not be cost-effective in the general US population 1. The compounded risk of multiple factors and their interactions is not fully defined, making personalized assessment critical.
A critical pitfall is failing to disaggregate racial/ethnic categories by country and region of origin. For example, early-generation immigrants from Eastern Europe represent a high-risk group despite being categorized as "non-Hispanic White" in epidemiologic studies 1. Similarly, Asian Americans and Hispanic Americans have vastly different risks depending on their specific country of origin.
The evidence strongly supports that gastric cancer screening should target high-risk populations starting at age 45 years, particularly when combined with colonoscopy for those selecting that colorectal cancer screening modality 1.