Parkinsonism and rest tremor secondary to supratentorial tumours sparing the basal ganglia.

Intracranial neoplasms are an uncommon cause of symptomatic Parkinsonism and rest tremor. We found an incidence of 0.3% in a prospective evaluation of 907 patients with supratentorial tumours. Eight patients with Parkinsonism and rest tremor secondary to supratentorial tumours sparing the basal ganglia are reported. Neuro-imaging revealed compression and distortion of the basal ganglia by large tumours which were identified histopathologically as meningiomas in four patients and as an epidermoid, a fibrillary astrocytoma, an anaplastic oligodendroglioma and a glioblastoma. Six patients underwent tumour removal by craniotomy, in two the histopathology was obtained by stereotactic biopsy. Four patients were free of Parkinsonian symptoms and signs on long-term follow-up. The possible pathophysiological mechanisms involved are discussed. Since some of these patients closely resemble cases of idiopathic Parkinson's disease, and the movement disorder can precede other symptoms and signs or will remain isolated in the further course, the diagnosis of an intracranial neoplasm was generally delayed in these patients. Increased awareness of this rare entity may lead to an earlier diagnosis. Early computed tomography in patients with Parkinsonism might help to detect these patients with a potentially curable cause of their condition.