Systemic lichenoid inflammation from immune checkpoint inhibition

Abstract Immune checkpoint inhibitor (ICI) therapy is highly effective in managing several malignancies, however ICI can induce unique toxicities known as immune related adverse events (irAEs). A wide range of dermatologic irAEs including localized lichenoid dermatitis have been reported, however extensive lichenoid inflammation involving both skin as well as the mucous membranes has not been reported. We report the case of a 39-year-old female with metastatic melanoma who developed progressive skin, esophageal and vulvar inflammation during immunotherapy with nivolumab. The treatment was well tolerated until the 9th cycle of treatment when diffuse lichenoid manifestations progressed rapidly over a period of weeks. Initially, skin changes were noted on extremities, soon followed by severe epigastric pain thereafter vulvar irritation that presented with mucosal changes. This diffuse lichenoid inflammation prompted discontinuation of nivolumab. Her symptoms were successfully managed by prednisone. This report of extensive lichenoid changes adds to the expanding manifestations of systemic irAEs.