Neuroimmune Crosstalk: Peripheral Nervous System Disorders After Immune Checkpoint Inhibitors

This study aimed to identify the frequency and types of peripheral nervous system involvement, associated clinical features, treatment options, and prognosis in patients receiving immune checkpoint inhibitors (ICIs) for the treatment of malignancy.

This is a retrospective cross-sectional study. We included the data of patients who presented to our electromyography laboratory with neurologic complaints and were using ICIs between January 2019 and August 2024. We retrieved all medical and electrophysiologic records. In patients with multiple examinations, the first appropriate examination was included. Demographic data, oncologic diagnoses, neurologic diagnoses, and medications used were extracted from patient files and are presented here.

During the study period, we reviewed the records of 31 patients. Seven patients were excluded. The rough prevalence of newly developed neurologic findings attributed to peripheral nervous system involvement after using ICIs was 8%. The most common peripheral complications were sensory or sensory-motor axonal polyneuropathy and myopathy. The most commonly associated medications for these neurologic manifestations were pembrolizumab, nivolumab, and atezolizumab. Nonambulatory patients received immunomodulatory therapy and demonstrated functional improvement.

ICIs have been increasingly used in cancer treatment and can cause immune-related effects. As demonstrated in our study, the most common peripheral nervous system involvement associated with ICIs is axonal polyneuropathy, followed by myopathy. The type of ICI, cancer type, and prior chemotherapeutic treatments the patients previously received may play a role in the occurrence of these neurologic complications.