Description

Paraneoplastic syndromes are remote complications of systemic malignancy that manifest as disorders of one or more physiological systems and include endocrinopathies, dermatological, haematological and neuromuscular disorders. Paraneoplastic neurological syndromes (PNS) are characterised by rapid progression of atypical neurological symptoms without an obvious aetiology and may occur more than two years prior to cancer diagnosis. Cellular mechanisms involve cell mediated and humoral immune reaction against antigens expressed by tumour cells but which cells of the nervous system also express. This leads to inflammation and neuronal destruction. Rapid recognition of PNS is essential to allow investigation of underlying malignancy or to institute appropriate treatment and follow up. This review highlights the importance of suspecting PNS as a differential diagnosis in patients presenting with unexplained focal neurology and starts with an illustrative case history of a 77 year-old woman who presented with bilateral VI nerve palsy, confusion and ataxia.