Paraneoplastic disorders of the nervous system

Abstract

Paraneoplastic neurologic disorders (PND) refer to an extensive group of syndromes that can affect any part of the nervous system by mechanisms that are mostly immune mediated (Table 1). PND are more frequent than previously considered, with an incidence that varies with tumor type. The tumors more frequently involved are small-cell lung cancer (SCLC, ~3% of patients develop PND), thymoma (15%), and the plasma cell dyscrasias associated with malignant monoclonal gammopathies (~5-15%). For solid tumors other than SCLC the incidence of PND is less than 1%. In 60% of patients, symptoms of PND precede the tumor diagnosis. The majority of these patients are first seen by neurologists who should be aware that prompt diagnosis and treatment of the tumor along with immunotherapy may stabilize or improve the PND.