classic paraneoplastic limbic encephalitis
Classic paraneoplastic limbic encephalitis is a rare neuroimmunological disorder characterized by the sudden onset of seizures, progressive memory impairment (which may develop into dementia) and psychiatric manifestations (e.g. depression, personality changes, loss of social inhibition) associated with cancer (most commonly small-cell carcinoma of the lung) in the absence of tumor cell invasion of the nervous system. Other reported features include ataxia, dystonia, paresthesia, tremors, paranoid ideation, and hallucinations. The presence of antibodies that act on neuronal antigens (such as anti-Hu, anti-Ma2, anti-amphiphysin) are typically observed.