Immune Checkpoint Inhibition for Pancreatic Cancer

Pancreatic cancer is one of the ten most lethal cancers with a mortality rate of 5.7 per 100,000 individuals worldwide. According to the disease stage, its 5-year survival rate is between 3% and 34%. Treatment options for pancreatic cancer are surgery, chemotherapy, radiotherapy, and immunotherapy. Immune checkpoint inhibitor therapy is a kind of immunotherapy. Immune checkpoints on T cells like cytotoxic T-lymphocyte-associated protein-4 (CTLA-4) and programmed cell death protein-1 (PD-1) suppress the immune system by attaching to their ligands on normal and/or tumor cells. This mechanism protects the body against immune system hyperactivity, especially in autoimmune diseases, but tumor cells can escape from immune responses by expressing these ligands to maintain in the body and to be safe against the immune system. Immune checkpoint inhibitors are immunotherapeutic drugs that bind to proteins in cancer cells to prevent them from suppressing the immune system. Immune checkpoint inhibitors may lead to some adverse effects like vitiligo, thyroiditis, adrenal insufficiency, and other ophthalmologic, hematologic, and respiratory problems. However, it has been shown that the combination of these therapies with each other or other therapeutic approaches could increase the safety and efficacy of this developing method. Here, we will review some trials that have been done or are ongoing about the advances and the effects of immune checkpoint inhibitors on patients with pancreatic cancer.