Gastric Intestinal Metaplasia and Helicobacter pylori Testing

Abstract

Introduction: Gastric Intestinal metaplasia (GIM) is a frequent precancerous lesion, with 6-10 fold increase in gastric cancer risk. Helicobacter pylori (H. pylori) is believed to be the cause of majority of intestinal-type gastric adenocarcinoma by causing chronic active gastritis, which may evolve to atrophic gastritis, IM, dysplasia, and cancer. Whether H. Pylori eradication leads to reversal of IM remains controversial. Since H. pylori exhibits tissue tropism, we believe that IM drives H.pylori out of the gastric mucosa. Biopsy alone for the detection of H. pylori may be less accurate in the context of IM, especially if biopsies fail to sample non-metaplastic tissue. Hence, another method of H. Pylori testing must be performed. Methods: A retrospective chart review was conducted using Electronic Medical Records (EMR) at one hospital. After Institutional Review Board approval, a list of patients with a histological diagnosis of GIM over the past 10 years was obtained. The EMR was reviewed for patients with biopsy proven gastric intestinal metaplasia and H. Pylori testing status was documented. Results: A total of 54 patients were identified with GIM. The median age was 68 year, 94.4% were male, 83.3% were Caucasian, 79.6% were present or former smokers. Documentation of pathologic testing for H. Pylori was found for all patients with 22.2% testing positive in pathology specimen. Of the remaining 42 patients, serologic testing was done in 19 % with 50% testing positive, 25% testing negative and 25% equivocal. There were 34 patients with GIM and H pylori negative biopsies who did not have serological testing done, 2 had empiric anti-H Pylori treatment and 2 had protocol biopsies done 2 years later. Both the patientswith equivocal results on serological testing had protocol biopsies. Only 25.9%npatients were treated for H. Pylori after the diagnosis of GIM. Conclusion: Our study shows that pathologic testing for H. Pylori was completed in almost all cases of GIM and only 22.2% of patients had H. Pylori identified from their biopsy. This is in accordance with our hypothesis that gastric biopsy has lower accuracy in the presence of IM because of inability of H. Pylori to grow on metaplastic tissue. H. Pylori eradication could reduce the risk of further development of dysplasia and subsequent gastric malignancy. Therefore, we recommend that patients with intestinal metaplasia should undergo additional diagnostic tests if the initial biopsy is negative for H. Pylori.Figure 1