Xinni Song

Abstract Immune checkpoint inhibitors (ICIs) are known to cause a wide spectrum of immune-related adverse events (irAEs). Among these, eosinophilic fasciitis (EF) is a rare, fibrosing disorder causing inflammatory infiltration of subcutaneous fat and fascia. It is characterized clinically by edema and subsequent induration and tightening of the skin and subcutaneous tissues. Several case reports have documented EF secondary to ICIs in patients on active treatment.