Immunotherapy for Cancer: Common Gastrointestinal, Liver, and Pancreatic Side Effects and Their Management

Cancer cells can block the activation of T lymphocytes by deploying inhibitory signals to cell surface receptors that downregulate the immune response. Immune checkpoint inhibitors (ICI) are monoclonal antibodies that regulate the immune response by acting on these receptors. The use of ICI has been successful for cancer types that do not respond well to conventional chemotherapy, showing clinical benefit in various advanced and metastatic cancers and supporting the promise of cancer immunotherapy. However, in some cases, these treatments are associated with immune-related adverse events, many of which affect the digestive system. The treatment of immune-related adverse events depends on the affected organ and the severity of symptoms. Here, we review the commonly used US FDA-approved ICI and briefly outline their mechanism of action. We also describe the resulting collateral effects on the gastrointestinal tract, liver, and pancreas and discuss their management and prognosis.