A Report of Polymorphous Toxic Erythema of Chemotherapy During Treatment with Enfortumab Vedotin for Metastatic Urothelial Cell Carcinoma

Abstract

Enfortumab vedotin (EV) is a novel drug targeting solid tumors expressing Nectin-4, such as metastatic urothelial carcinoma (mUC). While trials have supported its efficacy, there have also been early reports of cutaneous toxicity that have not yet been well characterized. Here, we report a case of a 60-year-old male who presented with burning, erythematous, and edematous plaques after receiving one cycle of EV as part of a Phase III clinical trial for treatment of his mUC. After a sixth cycle of treatment, he developed pruritic, erythematous, and hyperkeratotic papules with scattered tense vesicles across his extremities and trunk. These eruptions contain features suggestive of toxic erythema of chemotherapy (TEC). The first eruption resolved promptly with topical triamcinolone, whereas the second eruption required both topical triamcinolone and prednisone 1 mg/kg/day and resolved more slowly across 3 weeks. Although the two presentations had different morphologies, both can be described histologically as TEC. We therefore propose that one potential cutaneous eruption from EV therapy can be TEC and that it may have polymorphous presentations both across patients and within the same patient.