Lichen planopilaris associated with pembrolizumab in a patient with metastatic melanoma

FDG: fluorodeoxyglucose LPP: lichen planopilaris PET-CT: positron emission tomographye computed tomography PD-1: programmed cell death receptor 1 P embrolizumab, a programmed cell death receptor 1 (PD-1) inhibitor, has been used effectively for treatment of metastatic melanoma. Reported cutaneous adverse events ascribed to PD-1 inhibitors include lichenoid reactions such as lichen planus of the skin and oral mucosa, lichen planus pemphigoides, and lichenoid drug eruptions, as well as alopecia areata and vitiligo. We present a patient with metastatic melanoma who had lichen planopilaris (LPP) after receiving pembrolizumab. We find no previous report in the literature of LPP in association with PD-1 inhibitors.