Clin Gastroenterol Hepatol. 2023 Apr;21(4):878-890. doi: 10.1016/j.cgh.2022.10.004.Epub 2022 Oct 18.

Anusha Shirwaikar Thomas ¹, Stephen Hanauer ², Yinghong Wang ³

Author information

¹Department of Gastroenterology, Hepatology and Nutrition, The University of Texas MD Anderson Cancer Center, Houston, Texas.

²Division of Gastroenterology, Northwestern University Feinberg School of Medicine, Chicago, Illinois.

³Department of Gastroenterology, Hepatology and Nutrition, The University of Texas MD Anderson Cancer Center, Houston, Texas. Electronic address: ywang59@mdanderson.org.

Abstract

Immune checkpoint inhibitors have revolutionized management of advanced malignancies. However, their use is frequently complicated by immune related adverse events (irAEs), immune checkpoint inhibitor enterocolitis (IMEC) being the most common toxicity. IMEC is a distinct form of bowel inflammation that is highly reminiscent of idiopathic inflammatory bowel disorders (Crohn's disease, ulcerative colitis, and microscopic colitis). In this review, we highlight the similarities and differences in the pathophysiology, clinical presentation, evaluation, and management of these overlapping immune inflammatory bowel disorders. IMEC is an inflammatory bowel disease-like irAE that occurs as an outcome of disruption of intestinal immune surveillance and gut dysbiosis. Clinical and endoscopic presentation of both entities is strikingly similar, which often guides management. Though well established in inflammatory bowel disease, little is known about the long term outcomes of IMEC.