The authors present a striking case of a patient experiencing a lichenoid drug eruption secondary to immunotherapy, curiously sparing scarred skin from past burns. We observed vastly higher amounts of inflammatory lymphoid cells staining for PD-1; 70% in skin with a lichenoid drug reaction and 50% in scarred skin. The lack of a lichenoid reaction at sites of scarred skin may indicate that a basement membrane component may be causative for a lichenoid drug eruption.
Keywords: PD-1 inhibitor; immune-related adverse events; immunotherapy; lichenoid eruption; melanoma.
© 2023 The Authors. Australasian Journal of Dermatology published by John Wiley & Sons Australia, Ltd on behalf of Australasian College of Dermatologists.