Gastrointestinal disorders as immune-related adverse events.

Immune checkpoint inhibitors, such as cytotoxic T-lymphocyte antigen 4 inhibitors, programmed cell death 1 inhibitors and programmed cell death-ligand 1 inhibitors, have recently emerged as novel drugs in the anti-cancer therapy. Their use in different types of advanced cancer has shown good results and an increase in survival rates. However, immune-related adverse events (irAEs) are frequent and often require special care. IrAEs may affect all the organs, but they are most commonly seen in skin, lungs, endocrine glands and in the gastrointestinal tract where small bowel, colon, the liver and/or the pancreas can be involved. Despite being usually mild and self-resolving, irAEs may present in severe and life-threatening forms, causing the withdrawal of anti-cancer therapy. IrAEs, therefore, represent a challenging condition to manage that often requires the cooperation between the oncologists and the gastroenterologists in order to identify and treat them adequately.