A rare cutaneous manifestation of immune checkpoint inhibitor therapy.

Leukocytoclastic vasculitis can be an uncommon and/or underreported adverse event of immune checkpoint inhibitor therapy, an established cancer treatment option. Differentiation among other cutaneous manifestations of adverse medication reactions-such as Stevens-Johnson syndrome, erythema multiforme, and drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome-is crucial for guiding management.