Patterns of neurological adverse events among a retrospective cohort of patients receiving immune checkpoint inhibitors.

Neurological adverse events (NAEs) are infrequent immune checkpoint inhibitor (ICI) outcomes poorly characterized in extant research, complicating their clinical management. This study characterized the frequency, severity, patterning and timing of NAEs using a large retrospective registry, including all patients who received at least one dose of an ICI from 2/1/2011-4/7/2022 within our health network. Among 3137 patients, there were 54 NAEs (1.72% any grade; 0.8% grade 3-4). Most NAEs were peripheral (57.4%) versus central (42.6%). Melanoma and renal cell carcinoma were significantly associated with NAEs. The incidence of NAEs was rare though higher than many prior case estimates; the timing was consistent with other AEs. NAEs frequently occurred in tumor types known to favor brain metastases.