Neutrophil‐predominant bullous pemphigoid induced by checkpoint inhibitors: A case series

Abstract Checkpoint inhibitors have been revolutionary in the treatment of metastatic melanoma, non‐small‐cell lung cancer, and renal cell carcinoma. By restricting negative feedback of T‐cells, checkpoint inhibitors allow the immune system to identify and destroy malignant cells. This enhanced immune response is efficacious in the treatment of the aforementioned malignancies; however, it may lead to immune‐related adverse events. Bullous pemphigoid (BP) is a well‐documented cutaneous adverse reaction of checkpoint inhibitors, with a majority of cases reporting an eosinophil‐predominant or mixed inflammatory infiltrate. We report two cases of neutrophil‐predominant BP presenting in patients on checkpoint inhibitors.