A case of cytokine release syndrome associated with immune checkpoint inhibitor in patient with malignant melanoma

Abstract

A 46-year-old woman with a nodule in the left upper arm was referred to our clinic. She was diagnosed with malignant melanoma with left axillary lymph node metastasis, underwent surgical treatment, and subsequently received 12 months of adjuvant pembrolizumab. Three months after completing adjuvant therapy, she developed fatigue and was found to have an elevated serum lactate dehydrogenase level. Computed tomography (CT) revealed multiple liver metastases. Following the first and second cycles of ipilimumab plus nivolumab, she developed a high-grade fever exceeding 39℃, headache, and fatigue. No infectious source was identified. However, laboratory findings showed elevated levels of C-reactive protein, interleukin-6, and soluble interleukin-2 receptors. A diagnosis of cytokine release syndrome (CRS) was made. Although rare, CRS is a potentially life-threatening immune-related adverse event associated with immune checkpoint inhibitor (ICIs) therapy in melanoma. Here, we report a case of ICI-associated CRS and review the available literature.[Skin Cancer (Japan) 2026 ; 41 : 13-17]