Gastric Intestinal Metaplasia: Defining the Natural History

Abstract

Introduction: The management of intestinal metaplasia (IM), a pre-malignant condition and precursor to dysplasia and gastric carcinoma (GCa), is problematic because of paucity of data on its natural history, especially for the United States (US) population, and because of variance in guidelines. We aim to study the natural history of IM in the US and to identify potential risk factors for progression to GCa. Methods: A cohort of 9,000 consecutive patients with histologically confirmed IM were identified, and a subset from 2003-2004 was selected for this pilot study. Clinical, endoscopic, and histologic data was extracted, including demographics, BMI, symptoms, tobacco pack years, alcohol use, NSAID use, H. pylori, Barrett's esophagus, GERD symptoms, PPI use, anemia, blood group, and family history of GCa. Fisher's Exact Test (2-Tail) and the non-parametric Wilcoxon 2-Sample Test were used for analysis. Results: We identified 200 patients, with statistically equal distribution between genders. The majority were Caucasian (81.4%), with average age of 68, and mean BMI of 26.5. The majority of patients were symptomatic (82%) leading to endoscopy, including symptoms of: pain (43%), reflux (30%), GI bleeding (11%), and concern for GCa (8%). Sixty-one percent of patients were smokers, 18.6% of patients had H. pylori and 80.8% demonstrated eradication after treatment. Of the patients with documented blood type the majority, 54% had type A. Eleven percent of patients had a family history of GCa. Patients were followed for a mean of 4.1 years, and of those with clinical follow-up, 7%, (14) developed GCa. Those that lived (6), had a mean age of 67.5, while eight passed away from GCa with mean age of 75.6, and all were men. Conclusion: We found no association with H. pylori, obesity, or alcohol consumption and IM, and all other studied parameters did not appear to correlate. Of patients followed, 4% passed away from GCa, in contrast to SEER database prediction of 2% of deaths in US in 2014 due to GCa. This represents a significant, increase in risk of GCa death development in IM. The difference in gender and age was statistically significant for those with mortality. The progression from IM to GCa occurred in the US population and it appears the patients with IM were at higher risk than the general population. More frequent and rigorous endoscopic surveillance may be necessary, especially in elderly men if the increased risk is confirmed in the remainder of our cohort and by other studies.