Neurological Involvement in Merkel Cell Carcinoma

This clinical review examines the neurological complications associated with Merkel cell carcinoma (MCC), distinguishing between immune-mediated paraneoplastic syndromes and direct metastatic involvement. The text highlights that Lambert–Eaton myasthenic syndrome (LEMS) is the most frequent paraneoplastic manifestation and often appears before the cancer is officially diagnosed. Diagnostic protocols emphasize the use of paired serum and CSF antibody testing, specifically looking for VGCC, anti-Hu, and neurofilament antibodies to identify underlying malignancy. Management of these conditions primarily focuses on oncologic control, utilizing immune checkpoint inhibitors and stereotactic radiosurgery to improve patient outcomes. The author stresses the importance of differentiating structural brain disease from autoimmune reactions, as the therapeutic strategies for each differ significantly. Ultimately, the source provides a comprehensive framework for clinicians to identify, stage, and treat the complex nervous system interactions of this rare skin cancer. This episode is based on a paper written exclusively for the Weekly Neurology Deep Dive Podcast by Amer A. Ghavanini MD PhD FRCPC.