Cytokine release syndrome caused by dual immunotherapy with tremelimumab and durvalumab: A case report.

Cytokine release syndrome (CRS) is an acute systemic inflammatory syndrome characterized by fever and organ dysfunction. CRS is increasingly recognized as an immune-related adverse event caused by the use of immune checkpoint inhibitors (ICIs) to treat solid organ tumors. Herein, we report a life-threatening case of CRS that developed immediately after chemotherapy with tremelimumab and durvalumab in a patient with non-small-cell lung cancer. We administered high-dose corticosteroids and tocilizumab to the patient, which resulted in improvement. Regardless of the ICI class or immunoglobulin subclass, CRS should be considered when suspicious symptoms arise after ICI administration.