Autopsy case of opsoclonus-myoclonus-ataxia and cerebellar cognitive affective syndrome associated with small cell carcinoma of the lung.

We report an autopsy case of paraneoplastic opsoclonus-myoclonus-ataxia syndrome associated with small cell carcinoma of the lung. Chemotherapy and lung lobectomy resulted in complete tumor remission and disappearance of myoclonus. However, emotional and behavioral disturbances relapsed and remitted associated with exacerbation of truncal ataxia and ocular flutter, which responded favorably to prednisolone. At autopsy, after 2 years and 11 months of illness, there was no recurrence of cancer. Neuropathologically, only the cerebellum was affected, with diffuse loss of Purkinje cells and dentate neurons, suggesting that the paraneoplastic cerebellar involvement may be responsible for the cognitive affective symptoms in our patient.