Genital lichen sclerosus after nivolumab

We report a patient with metastatic melanoma undergoing treatment with nivolumab who developed genital lichen sclerosus. Nivolumab is a human IgG4 monoclonal antibody that inhibits PD1 (programmed cell death protein 1) activity. Even though nivolumab has a relatively good tolerance profile, it may induce severe immunologic toxicities. Immuno-related adverse events can affect several organs including the endocrine system, digestive system, kidneys, peripheral and central nervous systems, eyes, and skin. Cutaneous toxicities include vitiligo, lichen planus, psoriasis, and bullous pemphigoid. A history of genital symptoms should be considered as part of routine history in patients treated with nivolumab.