Recommended Protocol for Gastric Biopsy
The optimal gastric biopsy protocol follows the updated Sydney System with at least 5 biopsies from specific locations, with samples from the antrum/incisura and corpus placed in separately labeled containers. 1
Standard Biopsy Protocol
For General Diagnostic Purposes:
- Updated Sydney System protocol (5-biopsy approach):
- 2 biopsies from the antrum (within 2-3 cm from the pylorus, from lesser and greater curvature)
- 1 biopsy from the incisura angularis
- 2 biopsies from the body (1 from lesser curvature, ~4 cm proximal from the angle, and 1 from greater curvature, ~8 cm distal to cardia) 1
Specimen Handling:
- Samples should be placed in 2 separately labeled jars:
- Jar 1: "Antrum/incisura" specimens
- Jar 2: "Corpus" specimens 1
Special Considerations by Clinical Context
For H. pylori Detection:
- Follow the 5-biopsy Sydney System protocol as described above
- Obtaining gastric body biopsy specimens is especially important in patients using proton pump inhibitors or potassium-competitive acid blockers due to proximal migration of H. pylori organisms 1
- All specimens may be placed in the same jar for H. pylori detection alone 1
- Special staining is not routinely needed as H&E staining is usually sufficient 1
For High-Risk Patients (Gastric Intestinal Metaplasia/Preneoplasia):
- Follow the same 5-biopsy Sydney System protocol
- Separate antrum and gastric body biopsy specimens to allow assessment of extent, severity, and etiology of gastric atrophy and intestinal metaplasia 1
- Request histologic subtyping of gastric intestinal metaplasia as this improves prognostic value 1
For Gastric Ulcers:
- Take biopsies from both the base and edges of the ulcer 1, 2
- The positive biopsy rate increases to 95% when results from both rim and slough are combined 2
- Also biopsy the remainder of the stomach for H. pylori as previously described 1
For Gastric Polyps:
- Polyps should be biopsied or preferably resected to establish histologic diagnosis
- For solitary polyps: complete resection is preferred
- For multiple polyps: resect the largest polyp(s) and take representative samples from remaining polyps 1
- Consider biopsies of intervening mucosa for gastric atrophy, intestinal metaplasia, and H. pylori if clinical suspicion for hyperplastic or adenomatous polyps 1
Importance of the Incisura Angularis Biopsy
The incisura angularis biopsy is particularly important as:
- 8% of cases with atrophic gastritis and 3% with intestinal metaplasia would be missed without this biopsy 3
- The angulus, antrum (35%), and lesser curvature of the corpus (33%) show the highest prevalence of pre-malignant conditions 4
- Non-targeted biopsies from the lesser curvature have significantly higher yield compared to the greater curvature for diagnosing atrophic gastritis and intestinal metaplasia 4
Common Pitfalls to Avoid
Inadequate sampling: Taking too few biopsies reduces diagnostic yield. Always follow the 5-biopsy protocol.
Improper labeling: Failure to separately label antrum/incisura and corpus specimens can limit assessment of disease extent and severity.
Missing the incisura angularis: This site has high diagnostic yield and should not be overlooked.
Inadequate ulcer sampling: For gastric ulcers, both the rim and base should be sampled to maximize detection of malignancy.
Ignoring medication effects: In patients on acid-suppressing medications, H. pylori may migrate proximally, making corpus biopsies particularly important 1, 5.
By following this standardized protocol, clinicians can optimize the diagnostic yield of gastric biopsies while ensuring appropriate assessment of gastric pathology, particularly for conditions that may progress to gastric cancer.