Catatonia as a manifestation of paraneoplastic encephalopathy.

The psychopathological, electrophysiological, and pathological features of a 58-year-old woman suffering from anaplastic lung carcinoma with paraneoplastic encephalopathy are presented. The predominant behavioral manifestation was a catatonic syndrome that was partially responsive to clonazepam. Although a variety of neurological, psychiatric, and other causes of catatonia have been reported, this is the first reported case of catatonia caused by paraneoplastic encephalopathy.