What is the most common etiology of gastric nodules?

Most Common Etiology of Gastric Nodules

Hyperplastic polyps are the most common etiology of gastric nodules, accounting for approximately 46-53% of all gastric polypoid lesions, and are strongly associated with underlying chronic gastritis, particularly Helicobacter pylori infection. 1, 2

Epidemiology and Pathogenesis

• Hyperplastic polyps represent the predominant gastric nodular lesion in most patient populations, followed by fundic gland polyps (14%) and foveolar hyperplasia (18%). 2

• These lesions arise in the setting of abnormal gastric mucosa, with 85% of patients having underlying inflammatory mucosal pathology. 3

• The most common associated conditions include:

  • Active chronic H. pylori gastritis (25% of cases) 3
  • Reactive or chemical gastropathy (21%) 3
  • Metaplastic atrophic gastritis of autoimmune type (12%) or environmental type (8%) 3

Geographic and Temporal Variations

• Fundic gland polyps have become increasingly common in Western countries due to widespread proton pump inhibitor (PPI) use, though hyperplastic polyps remain the second most common type. 1

• The prevalence varies significantly based on local H. pylori infection rates and PPI therapy patterns. 4

Clinical Characteristics

• Hyperplastic polyps are most frequently located in the antrum (60% of cases), followed by the cardia. 2, 3

• They are multiple in 20% of patients and typically small, with 53% measuring ≤5 mm in largest dimension. 2

• When H. pylori is identified in surrounding mucosa, it is also present within the polyp tissue in 69% of cases, characterized by dense lymphoplasmacytic inflammation and intraepithelial neutrophils. 5

Critical Diagnostic Considerations

• Approximately 20% of endoscopically identified "polyps" have no definite pathological diagnosis, emphasizing the importance of histologic confirmation. 4

• Evaluation of surrounding gastric mucosa is essential, as 37% of patients with hyperplastic polyps have intestinal metaplasia, and 6% have synchronous or metachronous adenocarcinoma in the background mucosa. 3

• Hyperplastic polyps harbor dysplasia in 1.9-19% of cases, with focal intestinal metaplasia present in 16% and dysplasia in 4%. 6, 2, 3

Differential Diagnosis Context

When evaluating gastric nodules, the differential includes:

• Fundic gland polyps: Now most frequent in Western countries due to PPI use, but hyperplastic polyps remain second most common 1
• Adenomatous polyps: Less common but critical to identify, with 30% synchronous gastric adenocarcinoma rate 6
• Gastritis manifestations: Multiple uniform nodules may represent enlarged areae gastricae from gastritis rather than true polyps 7
• Gastrointestinal stromal tumors (GISTs): Subepithelial masses that appear as nodules but arise from deeper layers 7

Management Implications

• Testing for H. pylori infection is recommended in all cases of hyperplastic polyps, as the infection is present in 25-49% of cases. 6, 2

• Complete resection is mandatory for polyps >1 cm due to significant dysplasia risk, regardless of H. pylori status. 6

• Biopsy of nonpolypoid gastric mucosa during endoscopy is essential to identify underlying gastritis patterns and synchronous neoplasia. 3