Paraneoplastic neurologic disorders and neurologic complications of immune checkpoint inhibitors.

Paraneoplastic neurologic syndromes (PNS) are disorders resulting from an aberrant immune response against the nervous system, triggered by a tumor. Immune checkpoint inhibitor (ICI) cancer immunotherapies, enhance antitumor immunity by targeting immune checkpoint molecules on different cells, including immune and tumor cells. While ICIs improve cancer outcomes, these therapies can lead to immune-related adverse events (irAEs) in several systems including the nervous system. Neurologic irAEs may affect any level of the neuraxis, and, a subset of patients may present with syndromes resembling classic PNS. This chapter will discuss the epidemiology, pathogenesis, clinical manifestation, diagnostic approach, and treatment of PNS and neurologic irAEs.