Reconceptualization of immune checkpoint inhibitor-associated gastritis

Abstract

In recent years, with the extensive application of immunotherapy in clinical practice, it has achieved encouraging therapeutic effects. While enhancing clinical efficacy, however, it can also cause autoimmune damage, triggering immune-related adverse events (irAEs). Reports of immunotherapy-induced gastritis have been increasing annually, but due to its atypical clinical symptoms, early diag-nosis poses a certain challenge. Furthermore, it can lead to severe complications such as gastric bleeding, elevating the risk of adverse outcomes for solid tumor patients if immunotherapy is interrupted. Therefore, gaining a thorough under-standing of the pathogenesis, clinical manifestations, diagnostic criteria, and treatment of immune-related gastritis is of utmost importance for early identification, diagnosis, and treatment. Additionally, the treatment of immune-related gastritis should be personalized according to the specific condition of each patient. For patients with grade 2-3 irAEs, restarting immune checkpoint inhibitors (ICIs) therapy may be considered when symptoms subside to grade 0-1. When restarting ICIs therapy, it is often recommended to use different types of ICIs. For grade 4 irAEs, permanent discontinuation of the medication is necessary.

Keywords: Programmed cell death receptor-1; Programmed cell death-ligand 1; Cytotoxic T lymphocyte-associated antigen 4; Immune-related adverse events; Immune-related gastritis

Core Tip: With the widespread application of immunotherapy, the incidence of immune-related gastritis has increased than before. However, the diagnosis of immune-related gastritis is somewhat challenging due to its atypical clinical symptoms and lack of specific findings in serological tests. Although endoscopy and histopathological examination are valuable for immune-related gastritis diagnosis, differential diagnosis for different diseases (such as autoimmune gastritis) is still necessary. The treatment of immune-related gastritis should be individualized based on the patient's specific situation. The occurrence and management of immune-related adverse events (irAEs), as well as whether to continue treatment with immune checkpoint inhibitors (ICIs) after resolution, are major challenges in clinical practice. Studies have shown that for patients with grade 2-3 irAEs, ICI treatment can be considered for reinitiation when symptoms regress to grade 0-1, preferably using a different class of ICIs. For grade 4 irAEs, ICIs should be permanently discontinued.