免疫检查点抑制剂相关消化系统不良反应及处理OA

In recent years,immune checkpoint inhibitors(ICI)have been emerging as standardized therapeutic agents against malignant tumors,while immune-related adverse events(IrAE)caused by ICI have become more common with their increased use.Excessive activation of the immune system due to"antigen sharing"and"immune off-target effect"may be the underling mechanisms of IrAE.Immune-related colitis and liver injury are the two most common IrAE in digestive system.Clinicians need to identify IrAE early and initiate treatment promptly.Most patients with IrAE respond well to appropriate supportive management,with symptoms relieved or less frequency to develop severe complications.Patients with severe IrAE(classified as grade≥3)should discontinue ICI and start treatment with immunosuppressive agents,typically corticosteroids.Patients with IrAE respond well to corticosteroids treat-ment.For corticosteroid-refractory IrAE,other immunomodulatory drugs should be applied.Generally,ICI rechallenge may be consid-ered for grade 2 IrAE,while cautious reintroduction might be an option for grade 3 IrAEs.In contrast,multiple guidelines recommend permanent discontinuation of ICI for patients experiencing grade 4 IrAEs.The decision to rechallenge with ICI should be based on a risk-benefit assessment,considering factors such as tumor status,availability of alternative treatment options beyond ICI,and the severity of previous IrAE.Patients who undergo ICI rechallenge require closer monitoring and follow-up to facilitate early identification and management of recurrent IrAE.