Neurological side effects of checkpoint inhibitors

Abstract

In recent years the treatment of many tumor entities has been revolutionized by the use of modern immunotherapies with checkpoint inhibitors; however, good response rates are contrasted by many immune-mediated side effects. Neurological immune-mediated side effects are rare but often severe complications of checkpoint inhibitor treatment. Asystematic search in the PubMed and Web of Sciences databases was carried out for case reports and studies on neurological side effects during checkpoint inhibitor treatment. A total of 42articles on neurological side effects of checkpoint inhibitors with a total of 85 reported cases could be identified. The most frequently reported neurological side effects were myopathies, neuropathies, diseases of the neuromuscular endplates and encephalitides. Among those, encephalitides and myopathies with accompanying myocarditis were associated with the highest morbidity and mortality. Against the background of arapidly increasing use of checkpoint inhibitors, this article provides an overview of currently available reports on the clinical courses of neurological side effects. Controlled studies on the treatment of neurological side effects are lacking. From case studies it can be assumed that early steroid treatment increases the probability of acomplete remission of neurological symptoms. Typical symptom constellations must therefore be rapidly recognized and an immunosuppressive treatment must be initiated.