The American Gastroenterological Association (AGA) recently published clinical practice guidelines for managing gastric intestinal metaplasia (GIM).
The guidelines are the first of their kind to be published in the United States, according to lead author Samir Gupta, MD, of the University of California San Diego, and colleagues. The panelists suggested that the guidelines may help standardize decision making in a common clinical scenario.
“GIM has been considered as one specific marker to identify patients who might benefit from surveillance because it has been associated with increased risk for gastric cancer and is routinely encountered in clinical practice,” the panelists wrote in Gastroenterology.
The guideline panel was composed of three gastroenterologists, two guideline methodologist trainees, and three GRADE experts. Recommendations were based on the AGA guideline development process, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, best practices set forth by the Academy of Medicine, and a technical review.
“Given the paucity of robust direct data on GIM in the U.S., evidence from all regions of the world was considered relevant in the evidence-gathering phase,” the panelists wrote (Gastroenterology. 2019 Dec 6. doi: 10.1053/j.gastro.2019.12.003).
Based on available evidence, the expert panel developed three clinical recommendations.
First, the panelists recommended that clinicians test all patients with GIM for Helicobacter pylori, followed by eradication, over no testing and eradication. This recommendation was strong and based on moderate quality evidence from 22 studies, including 7 randomized controlled trials. These studies showed that, compared with placebo, eradication of H. pylori was associated with a 32% pooled relative risk reduction in gastric cancer and a 33% pooled relative risk reduction in gastric cancer mortality among patients with or without GIM. The pooled relative risk reduction rate was similar in analyses solely composed of individuals with GIM, the panelists noted, whereas mortality data restricted to individuals with GIM were lacking.
“Overall, the known strong association of H. pylori with risk for incident gastric cancer and the technical review’s findings, which reinforce the evidence of reduced risk for incident gastric cancer after H. pylori eradication, supports the AGA recommendation to test for and eradicate H. pylori,” the panelists wrote.
The second recommendation, which was conditional and based on very low quality evidence, advised against routine use of endoscopic surveillance for patients with GIM. Still, surveillance may be considered for patients with higher risk of gastric cancer, including those with incomplete and/or extensive GIM, a family history of gastric cancer, racial/ethnic minorities, and immigrants from high incidence regions, the panelists wrote.
“Although the technical review did not find evidence supporting increased risk for gastric cancer among racial/ethnic minorities or immigrants with documented GIM, an overall increased risk for gastric cancer (irrespective of presence/absence of GIM) has been established among these groups, and may be considered as part of decision making regarding surveillance,” the panelists wrote.
The third and final recommendation was also conditional and based on very weak evidence; the panelists recommended against routine short-interval repeat endoscopy for the purpose of risk stratification.
“The technical review found no direct evidence to support the impact of short-interval (less than 12 months) repeat upper endoscopy among patients with incidental GIM on patient-important outcomes,” the panelists wrote.
However, the guidelines note that patients with potentially elevated risk profiles, such as patients with a family history of gastric cancer, “may reasonably elect for repeat endoscopy within 1 year for risk stratification.”
Comparing these guidelines with those from other organizations, such as the European Society of Gastrointestinal Endoscopy (ESGE), the panelists concluded that recommendations across organizations are “generally similar.”
Finally, the panelists outlined relevant knowledge gaps and pointed to future research topics. For instance, data are scarce comparing outcomes in relation to surveillance versus no surveillance among patients with GIM; and biomarkers such as pepsinogen levels, which are used in Asian countries for risk stratification of gastric cancer, have been studied minimally in the United States.
Guideline development was funded by the AGA. The panelists disclosed no conflicts of interest.