A Case of Pembrolizumab-Induced Toxic Epidermal Necrolysis / 대한피부과학회지

ABSTRACT

Pembrolizumab is an immune checkpoint inhibitor that selectively blocks the programmed cell death (PD)-1 receptor. Although it has a dramatic effect on the treatment of advanced malignancies, instability of immune tolerance may cause immune-related adverse events in the skin. A 62-year-old male with a history of metastatic urothelial carcinoma was referred to the dermatology department and presented with a widespread mucocutaneous rash. Itching appeared 7 days after the first administration of pembrolizumab, and on the third day after the second administration, an erythematous maculopapular rash that coalesced into large flaccid bullae on the whole body with a positive Nikolsky’s sign developed. A biopsy revealed a subepidermal bulla with basal keratinocyte necrosis. Pembrolizumab was discontinued due to the diagnosis of toxic epidermal necrolysis (TEN), and intravenous methylprednisolone was started. Herein, we report a case of TEN induced by pembrolizumab to highlight immune-related cutaneous adverse events in patients receiving anti-PD-1 therapy.