Inverse lichenoid drug eruption associated with nivolumab

Nivolumab is a fully human IgG4 anti–programmed cell death protein 1 (PD-1) receptor antibody that is approved by the US Food and Drug Administration for the treatment of metastatic melanoma, refractory non–small cell lung cancer, angiogenesis inhibitor–resistant renal cell carcinoma, and stem cell transplant–resistant classical Hodgkin lymphoma. The blockade of the PD-1 and programmed cell death ligand 1 pathway, as well as other immune checkpoint receptors, functions to inhibit a negative regulator of T-cell activation, thereby activating T cells and promoting antitumor activity.1 Along with pembrolizumab, another PD-1 receptor inhibitor, these agents are promising in the treatment of many different cancer entities but have been associated with a wide array of cutaneous adverse effects. We report an unusual case of a lichenoid drug eruption, with a distinct inverse distribution in the groin area secondary to nivolumab.