Cutaneous Immune-Related Adverse Events Secondary to Immune Checkpoint Inhibitors and Their Management

Immune checkpoint inhibitors (CPIs) are highly effective in the treatment of various cancers. Immunotherapy enhances antitumor activity by relieving inhibition of T cells responsible for immune surveillance. However, overactivation of T cells leads to immune-related adverse events (irAE), of which cutaneous adverse events are the most common. Examples include pruritus and maculopapular eruption most commonly, psoriasis and bullous dermatoses less commonly, and, rarely, severe, life-threatening eruptions such as Stevens-Johnson Syndrome or Toxic Epidermal Necrolysis. Many of these are autoimmune in nature, and these may present de novo or as recurrence of pre-existing disease. In order to maximize the therapeutic potential of CPIs, it is essential to recognize and effectively manage cutaneous irAE, which can otherwise lead to treatment interruption or discontinuation. This review summarizes the presentation and management of dermatologic adverse events secondary to immune dysregulation as a result of immune checkpoint inhibitor therapy, including the most common (maculopapular eruption, pruritus, lichenoid dermatitis, and vitiligo), less common (psoriasis, bullous pemphigoid, erythema multiforme, eczematous dermatitis, alopecia areata, and granulo-matous and neutrophilic dermatoses), and severe (acute generalized exanthematous pustulosis [AGEP], drug reaction with eosinophilia and systemic symptoms [DRESS], and Stevens-Johnson syndrome or toxic epidermal necrolysis [SJS/TEN]), as well as exacerbation of pre-existing cutaneous autoimmune disease (subacute cutaneous lupus erythematosus, dermatomyositis, eosinophilic fasciitis, leukocytoclastic vasculitis, and scleroderma-like reaction).