Introduction: Among immune-related adverse events (irAE) associated with immune checkpoint inhibitors (ICI), immune-related gastritis (IMG) has been rarely described in the literature and has not yet been well characterized. This systematic scoping review aimed to characterize IMG in terms of precipitating agents, clinical presentations, and prognosis.
Methods: Following the PRISMA Extension for Scoping Reviews, we searched MEDLINE and EMBASE for all peer-reviewed articles using keywords including “gastritis”, “immune checkpoint inhibitor”, and “immune-related adverse event” from their inception to December 28, 2021.
Results: 22 articles, including five observational studies and 17 case reports and case series, were included. Nivolumab, pembrolizumab, and combination therapy with those and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) inhibitor (ipilimumab) were commonly used in those with IMG. 59.8% had epigastric pain, and 50% had erosive gastritis. 87.5% had Common Terminology Criteria for Adverse Events (CTCAE) grade 3 gastritis, and 91.2% received corticosteroids. Recurrence was noted in 16.7%, and only one expiration was noted. 4.3% had positive helicobacter pylori (H. pylori) and cytomegalovirus from the gastric specimen.
Discussion: Similar to immune-related colitis, patients with IMG may have a favorable prognosis with a better response to ICIs if treated appropriately. The diagnosis of IMG is made by exclusion, and a thorough workup is necessary to rule out concurrent H. pylori and cytomegalovirus involvement. Further studies are critical for a better understanding of this complication.
