Paraneoplastic neurological syndromes

Abstract

Purpose of review: This review describes relevant advances in paraneoplastic neurological syndromes (PNS) with emphasis on particular syndromes and the impact of antibodies against surface antigens in their management.

Recent findings: PNS may present with symptoms that do not raise the suspicion of a paraneoplastic origin. The best example is anti-N-methyl-D-aspartate receptor encephalitis that in adult women frequently associates with ovarian teratoma. An electroencephalogram pattern described as 'extreme delta brush' was recently identified in 30% of patients with this disorder. Isolated myelopathy may have a paraneoplastic origin associated with amphiphysin or CV2 (CRMP5) antibodies. Jaw dystonia and laryngospasm can be the predominant symptom of the brainstem encephalitis associated with Ri antibodies. γ-Aminobutyric acid (GABA)(B) receptor antibodies are the most common antibodies found in patients with limbic encephalitis and small cell lung cancer, and contactin-associated protein 2 antibodies in patients with Morvan's syndrome and thymoma. Lastly, a recent study identified delta/notch-like epidermal growth factor-related receptor (DNER) as the target antigen of Tr antibodies, a marker of cerebellar ataxia and Hodgkin's lymphoma.

Summary: The number of antibodies relevant to PNS is now expanded to those against surface antigens. These antibodies do not confirm the paraneoplastic origin of the syndrome but predict a better response to immunotherapy.