Guillain–Barre Syndrome-Like Polyneuropathy Induced by Immune Checkpoint Inhibitors: A Case Report

Over the past decade, immune checkpoint inhibitors (ICIs) have emerged as a crucial therapeutic option for treating various malignancies. Nivolumab, an ICI, is a monoclonal antibody directed against programmed cell death protein 1. However, many studies indicate that ICIs can lead to various immune-related adverse events (irAEs), with neurological irAEs accounting for approximately 1%-5% of these cases. Neurological adverse events such as Guillain-Barre syndrome (GBS) are rare but life threatening. This report presents the case of a 72-year-old male diagnosed with sarcomatoid squamous cell carcinoma of the trachea, who was admitted with rapid-onset weakness of the upper limbs 7 days following the latest nivolumab treatment. These symptoms progressed quickly to quadriplegia and respiratory failure, requiring intubation and mechanical ventilation. Serum antiganglioside antibodies were positive for immunoglobulin (Ig) M-GM1, IgM-GD1b, and IgG-GM3. His clinical symptoms improved significantly after steroid and intravenous immunoglobulin treatment. This rare and atypical case highlights the complexity of ICI-related GBS. Early recognition of associated symptoms is crucial for timely and appropriate treatment.