Cytokine release syndrome induced by dabrafenib and trametinib therapy in BRAF V600E-mutant non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) with BRAF V600E mutations is responsive to targeted therapies, such as dabrafenib and trametinib. However, these treatments can lead to serious adverse events, including cytokine release syndrome (CRS). Herein, we report the case of a 75-year-old man with stage IVB NSCLC and a BRAF V600E mutation who developed severe CRS, manifesting hepatic and renal dysfunction, following treatment with dabrafenib and trametinib. Despite initial fever management, the patient's renal function deteriorated rapidly, necessitating hemodialysis. Elevated cytokine levels, including interleukin-6, interferon-γ, and tumor necrosis factor α, were detected. The patient was treated with steroid pulse therapy, which resulted in fever resolution, and his renal function gradually improved. Hemodialysis was discontinued as renal function recovered. This case underscores the importance for early recognition and management of CRS in patients receiving targeted therapies. Prompt intervention with steroids may prevent CRS progression and mitigate associated organ dysfunction. Further investigation is required to clarify the mechanisms of CRS in patients receiving targeted therapy, particularly in the absence of prior immune checkpoint inhibitor use.