Safe Transition to Pembrolizumab followingIpilimumab-Induced Guillain-Barré Syndrome:A Case Report and Review of the Literature

Immune checkpoint inhibitors are novel therapies with indications for treating several solid cancers. They areassociated with immune-related adverse events, which are generally well tolerated. Though rare, severe side effects may be life-threatening. One such adverse event is Guillain-Barré syndrome, which requires cessation of the immunotherapy andintravenous immunoglobulin and/or high-dose steroids to treat. No recommendations have been published regarding restartingcancer treatment after development of immunotherapy-induced Guillain-Barré syndrome.Case Presentation. A 71-year-oldgentleman with recurrent, stage IIIB melanoma was started on ipilimumab (cytotoxic T lymphocyte antigen-4 inhibitor) foradjuvant treatment following radical neck dissection and radiation therapy. After completing his third cycle of ipilimumab, hedeveloped rapidly progressive ascending paralysis. He was diagnosed with ipilimumab-induced atypical Guillain-Barrésyndrome and was treated with intravenous immunoglobulin and corticosteroids. Ipilimumab was discontinued, and the patientwas monitored via surveillance imaging, as there was no evidence of active disease at that time. Several months later, he wasfound to have recurrent disease involving the lung, requiring right lower lobectomy. Restaging revealed thoracic lymph nodeinvolvement, and he was then started on pembrolizumab (programmed cell death protein-1 inhibitor). He experienced acomplete tumoral response to pembrolizumab, and he tolerated treatment well without recurrent weakness.Conclusions.Guillain-Barré syndrome is a rare but severe complication associated with immunotherapy. Ourfindings suggest that in patientswith a history of ipilimumab-induced Guillain-Barré syndrome, pembrolizumab may possibly be a safe and effective alternativefor cancer therapy