P11.66.A Immune checkpoint inhibitors related peripheral nerve disorders: clinical and electrophysiological particularities

Abstract Background The immune-checkpoint inhibitors (ICIs) announced a new era in cancer treatment allowing long-term survival advanced cancers. However, immune related adverse events impose limitations being one of the main challenges when dealing with ICI treated patients. Neurologic toxicities have unique presentations and can progress rapidly, requiring prompt recognition. Among them, ICI-related peripheral nerve disorders are highly heterogeneous, profoundly debilitating, insufficiently explored. Material Methods We reviewed clinical electrodiagnostic features retrospective cohort patients hospitalized our centre for neuropathies. applied EFNS 2021 criteria neuropathies we researched outcome according to received. Results included 16 patients: 4 men 12 women, median age 61 years (31-72) by anti-PD1 monotherapy (10) or antiCTLA4-antiPD1 combination (6). Median delay from ICIs initiation neuropathy symptoms was 58,5 days (4 cycles), it seemed lower group (median 33,5 vs 81,5 p=0,02). Half presented concurrent non-neurological irAE. CSF inflammatory 56% cases, pleocytosis seen 57% these. Cranial involvement rare (3/16) most frequent phenotype demyelinating polyneuropathy fulfilling EMG 10 cases. other 6 non-length dependent sensory neuropathy, (3) dysautonomic (1) motor incomplete (2). stopped, steroids were first line all 12/16 received additional iv immunoglobulin. Supplementary immunomodulation (cyclophosphamide, tocilizumab) required 2 75% improved within 4.5 months, decrease mRS points. Noteworthy, rechallenge antiPD1 proposed single relapse. Conclusion Our series expand knowledge on electrophysiological improving their recognition practice. Moreover, findings argue benefit adding immunoglobulin as different phenotypes