Pityriasis rubra pilaris–like erythroderma in the setting of pembrolizumab therapy responsive to acitretin

Numerous cutaneous adverse effects have been associated with programmed death 1 (PD-1) inhibitors including maculopapular eruptions, pruritus, eczema, lichenoid reactions, leukoderma, psoriasis, sarcoidosis, immunobullous disorders, and Stevens-Johnson syndrome.1,2 Here we report the first case, to our knowledge, of pityriasis rubra pilaris (PRP)-like erythroderma in the setting of anti–PD-1 therapy responsive to acitretin and topical steroids.