Primary central nervous system lymphoma presenting as choreoathetosis

A 49-year-old man developed right hemiparesis and choreoathetosis involving his right upper and lower extremities. His choreoathetosis worsened with attempts at action or posture. Neurological examination showed mild dysarthria, and right upper motor neuron facial palsy. His gait was almost normal. There was no loss of pain sensation or proprioception. Brain MRIs showed high-intensity areas in the left cerebral peduncle, subthalamic nucleus, thalamus and adjacent posterior limb of internal …