Management Considerations for Immune Checkpoint Inhibitor-Induced Enterocolitis Based on Management of Inflammatory Bowel Disease

Background: Immune checkpoint inhibitor therapy has significantly improved the outcomes of various advanced malignancies that were deemed unruly prior to its invention. Immune-mediated diarrhea and enterocolitis are among the most frequently encountered adverse events of immune checkpoint inhibitor therapy. Given the increasing use of these therapies in the treatment of an ever-growing number of malignancies, providing appropriate treatment for such adverse effects has become crucial. Methods: In this review, we summarize the current body of evidence concerning the management of immune-mediated diarrhea and enterocolitis. Additionally, management of immune-mediated diarrhea and enterocolitis is likened to that of inflammatory bowel disease, given the resemblance between both entities in pathogenesis and clinical features. Reviewing the literature raised several points regarding this devastating toxicity that still need further investigation by future efforts. Results: Endoscopic and histologic evaluation is pivotal in the assessment of immune-mediated diarrhea and enterocolitis and provides vital information regarding the severity of the disease to guide treatment. Corticosteroids are the main therapy for immune-mediated diarrhea and enterocolitis, with infliximab and vedolizumab as second-line agents. Recently, fecal microbiota transplantation has emerged as a treatment option for immune-mediated diarrhea and enterocolitis that is refractory to corticosteroids. Restarting immune checkpoint inhibitor therapy after resolution of immune-mediated diarrhea and enterocolitis carries a risk of recurrence that is mostly controllable with current immune-suppressive treatment. Conclusions: Lastly, we propose a management algorithm for immune-mediated diarrhea and enterocolitis. Prospective research, preferably as collaborative efforts from oncology and gastroenterology specialists, is needed to refine the management of immune-mediated diarrhea and enterocolitis.