Skin reactions to immune checkpoint inhibitors

The novelty of immune checkpoint inhibitors has only recently led to the characterization of cutaneous adverse events (AEs). This, along with the substantial rate of cutaneous reactions, has left many clinicians without sufficient familiarity to diagnose and treat. Pruritus and rash are among the top five immune-related AEs reported in clinical trials for this class of therapy. Incidence varies between 35 and 50% for cutaneous AEs among the three FDA-approved drugs. Although only 2% are reported as grade 3 or 4 events, the quality of life impact can be significant for these patients and is best described in ipilimumab trials. 43.5% of ipilimumab patients have a cutaneous AE and, at our institution, 20% of them had a dose interruption as a result. This means potentially 9% of patients having dose interruption of ipilimumab because of their cutaneous AEs. In the following chapter, we will review the categories of these drugs, common cutaneous effects, their grading, and management options.