Severe eczematoid and lichenoid eruption with full-thickness epidermal necrosis developing from metastatic urothelial cancer treated with enfortumab vedotin.

Enfortumab vedotin (EV) is a novel, fully humanized monoclonal antibody-drug conjugate composed of an anti-Nectin-4 antibody joined to monomethyl auristatin E. In this report, we described a case of a severe eczematoid and lichenoid eruption with full-thickness epidermal necrosis developing in patients with metastatic urothelial cancer treated with EV. Because phase II and phase III clinical studies are ongoing, in the future, substantial amounts of EV are expected to be used for the treatment of metastatic urothelial cancer. Therefore, understanding the mechanisms of drug eruption caused by EV is important for oncologists as well as dermatologists.