Primary brain lymphoma presenting as Parkinson's disease.

Neoplasm is an uncommon cause of a parkinsonian syndrome. We report a woman with primary brain B-cell lymphoma presenting as Parkinson's disease. After 1 year of the illness, CT and MRI showed lesions without mass effect in the basal ganglia and corpus callosum. The patient did not respond to levodopa and right cerebellar and brain-stem signs appeared, which prompted further neuroimaging, showing an increase in size of the lesions and a right cerebellar and pontine mass. Stereotactic biopsy of the basal ganglia showed high-grade B-cell lymphoma. Despite the basal ganglia frequently being involved in lymphoma of the brain, presentation with typical or atypical parkinsonism is exceptional.