Neurological complications of immune checkpoint inhibitor therapy: a multidisciplinary case review

   Immunotherapy using immune checkpoint inhibitors (ICIs) has demonstrated efficacy in treating a wide range of oncological diseases, but the use of this group of drugs is associated with the risk of developing serious immune-related adverse events (irAEs). Although relatively rare, neurological complications associated with ICI use are often life-threatening. The most common of these include myositis, myasthenia (with or with-out myositis), peripheral neuropathies, including Guillain–Barre syndrome, autoimmune encephalitis, myelitis, and demyelinating syndromes. This article presents five clinical observations of the development of neurological complications against the background of the use of anti-PD-1 inhibitors (pembrolizumab, nivolumab) as monotherapy or in combination with an anti-CTLA-4 inhibitor (ipilimumab). The cases presented were diagnosed with transverse myelitis, peripheral neuropathies meeting the diagnostic criteria for chronic inflammatory demyelinating polyneuropathy, and myositis, including in combination with myasthenia gravis. To relieve these conditions, glucocorticoids were used in the form of pulse therapy followed by oral administration, high-volume plasmapheresis, and cytostatic drugs. The treatment provided resulted in marked clinical improvement. The observations presented emphasise the importance of early diagnosis and effective treatment of irAEs as well as a multidisciplinary approach to the management of such patients. To date, the problems of selecting the optimal management strategy for irAEs and assessing the safety of subsequent ICIs use remain relevant and require further prospective studies.

   In addition to demonstrating the importance of a multidisciplinary approach, the purpose of presenting these observations is to raise awareness among neurologists about neurological immune-related adverse events caused by ICI therapy.

   The relevance of this task is determined by the fact that the widespread introduction of ICI into clinical practice for the treatment of various malignant neoplasms will inevitably lead to an increase in such cases in neurological practice, which predetermines the need for neurologists to be prepared to diagnose and manage such patients.

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