Lichenoid drug reaction after ipilimumab/nivolumab combination therapy: A case report.

Nivolumab (PD-1 inhibitor) and ipilumumab (CTLA-4 inhibitor) are recently approved checkpoint inhibitors for treatment of non-small cell lung cancer. Immune-related adverse events related to the usage of checkpoint inhibitors are growing with their popularity. We present the case of a patient in combination treatment of nivolumab and ipilimumab who developed a lichenoid drug reaction, notable because it worsened to a bullous lichenoid drug reaction. Treatment with prednisone and withdrawal of checkpoint inhibitors aided in clinical resolution. Initial presentation of a lichenoid reaction that progressed to a bullous, desquamated presentation indicates the possibility of the prodromal rash progressing to a Stevens-Johnson Syndrome-like dermatosis. When dermatologists are consulted for rashes developed during checkpoint-inhibitor therapy, they should be aware that early treatment may prevent progression to bullae formation and desquamation and develop their treatment plans with this in mind.