Immune checkpoint inhibitors associated inflammatory disease of central nervous system: Case report and systemic review

The use of immune checkpoint inhibitors (ICIs) has greatly improved the outcomes of cancer. However, ICI-induced immune-related adverse events have been reported, among which neurological immune-related adverse events are rare but potentially life-threatening. To analyze the characteristics of ICI-induced inflammatory disease of the central nervous system (CNS), we reported the first case induced by tislelizumab and conducted a systematic review of 33 cases. A 65-year-old male patient who received 4 cycles of tislelizumab for lung squamous carcinoma developed myelitis, demyelinating encephalopathy, and peripheral neuropathy overlap syndrome. Case reports and case series that described ICI-associated inflammatory disease of the CNS in the PubMed and Embase databases were searched up to October 2022. The patient was diagnosed with ICI-associated neuroimmune overlap syndrome, including myelitis, peripheral neuropathy, and multifocal demyelinating encephalopathy. The patient was treated with intravenous methylprednisolone. The symptoms alleviated gradually. Twenty-six publications that described 33 cases with ICI-associated inflammatory disease of the CNS were reviewed. In addition to the present case, only 8 cases with both brain and spinal cord lesions induced by ICIs were reported. Intravenous steroids were the first-line therapy, while plasmapheresis, intravenous immunoglobulin, cyclophosphamide, and some monoclonal antibodies may be effective for steroid-refractory neurological immune-related adverse events. Thirteen patients experienced relapse, and 4 patients died, one of whom committed suicide. ICI-associated inflammatory disease of the CNS is very rare, but we should be aware of and detect it to treat timely manner and achieve a good prognosis.