Incidence and spectrum of paraneoplastic neurological syndromes: single center study.

Paraneoplastic neurological syndromes (PNS) are remote effects of cancer. They are much less common, but are nevertheless important because they cause severe neurological morbidity and mortality. The present cases were studied to characterize the clinical features of patients of suspected PNS and to study their association with different types of tumors. In this study conducted from a super speciality teaching institute from South India, forty five (incidence-0.25%) patients were diagnosed with PNS based on the clinical data. They were subdivided into two groups patients with central nervous system (CNS) manifestations and those with neuromuscular manifestations. Immunological markers were assessed in a subset of patients. Majority of them (75.6%) were above 40 years. There was no sex predilection and a chronic presentation was common (42.2%). While more than half had involvement of peripheral nervous system (64.4%), CNS manifestations were present in 16 (35.6%) cases. Immunological markers were present in 10 out of 14 (58.8%) patients. Classic PNS was seen 22 cases (48.9%), while 23 (51.1%) were non classical. Most common tumor was lung cancer followed by myeloma and breast carcinoma. Present study construed that, in patients with neurological syndromes of unknown cause, search should be focused for occult malignancy based on the phenotype and onconeural antibodies, targeting the lung and breast in particular.