Purpose of review: To describe specificities and new advances in paraneoplastic neurologic syndromes (PNSs).
Recent findings: Paraneoplastic neurologic syndromes are defined as neurologic syndromes of unknown cause that often antedate the diagnosis of an underlying, usually not clinically evident, cancer. In the last 2 decades, the discovery that many PNSs are associated with antibodies against neural antigens expressed by the tumor has suggested that some PNSs are immune-mediated. PNSs are rare and occur in less than 1% of patients with cancer. However, the diagnosis and treatment are important because the disability caused by the PNS is often severe, and the correct diagnosis usually leads to the discover of a small tumor with high chances of being cured.
Summary: There is increasing recognition of an extensive variety of PNSs and of several paraneoplastic antibodies as clinical markers of these disorders. Basic immunologic studies support the pathogenic role of some of these antibodies, and basic molecular studies support the role of some antigens in neuronal degeneration and tumoral growth.