Immune checkpoint inhibitor related enterocolitis

Immune checkpoint inhibitors (ICI) have been rapidly extended their indication in various cancer types. On the other hand, immune-related adverse event (irAE) is observed in some cases and sometime causes fatal outcome. Enterocolitis is one of the major irAE, especially in the case treated with anti-CTLA-4 antibody. Although the combination therapy of anti-CTLA-4 antibody and anti-PD-1 antibody has shown clinical benefit in some cancer types, a risk of enterocolitis is higher than monotherapy. Accumulated evidence has revealed the clinical features of enterocolitis caused by anti-CTLA-4 antibody and anti-PD-1/PD-L1 antibody. We summarize recent knowledge and discuss future perspectives.