Autoimmune Movement Disorders Complicating Treatment with Immune Checkpoint Inhibitors

BackgroundImmune checkpoint inhibitors (ICI) may trigger autoimmune neurological conditions, including movement disorders (MD).ObjectivesThe aim of this study was to characterize MDs occurring as immune-related adverse events (irAEs) of ICIs.MethodsA systematic literature review of case reports/series of MDs as irAEs of ICIs was performed.ResultsOf 5682 eligible papers, 26 articles with 28 patients were included. MDs occur as a rare complication of cancer immunotherapy with heterogeneous clinical presentations and in most cases in association with other irAEs. Inflammatory basal ganglia T2/fluid attenuated inversion recovery abnormalities are rarely observed, but brain imaging is frequently unrevealing. Cerebrospinal fluid findings are frequently suggestive of inflammation. Half of cases are associated with a wide range of autoantibodies. Steroids and ICI withdrawal usually lead to improvement, even though some patients experienced relapses or a severe clinical course.ConclusionMDs are a rare complication of ICIs that should be promptly recognized to offer patients a correct diagnosis and treatment.