Primary nodular meningeal glioma mimicking metastatic tumor of the cerebellum with diffuse infra- and supratentorial leptomeningeal spread.

A 62-year-old man presented with acute headache, blurred and double vision, nausea, and ataxia. Magnetic resonance imaging showed an enhancing mass on the inferior aspect of the right cerebellar hemisphere as well as a thin, widespread leptomeningeal enhancement and T2-weighted hyperintense lesions in the left occipital lobe and both thalami. Lumbar puncture revealed clusters of anaplastic cells. Therefore, metastatic tumor of unknown origin was suggested. Despite whole brain irradiation and intrathecal chemotherapy the patient deteriorated gradually and died four months later. Post-mortem examination of the brain revealed a nodular, high-grade astrocytic tumor within the subarachnoid space on the lower portion of the right cerebellar hemisphere. Diffuse leptomeningeal spread was noted, but cerebellar parenchyma was not infiltrated.