[Elderly patient with cerebellar malignant astrocytoma].

Malignant cerebellar astrocytoma is very rare and the prognosis is extremely poor. We report herein the case of an elderly patient with malignant cerebellar astrocytoma. This 80-year-old man initially presented with dizziness and ataxia of the right hand. Metastatic cerebellar tumor was diagnosed on first admission, based on a past history of colon cancer treated by surgery and magnetic resonance imaging (MRI) findings supporting the diagnosis of metastasis. The patient underwent gamma knife surgery (20 Gy) and was discharged. Follow-up after discharge was insufficient. Two years after gamma knife surgery, he returned to our hospital complaining of dizziness, headache, and right limb ataxia. MRI revealed a cystic mass in the right cerebellar hemisphere, and the lesion was removed by right suboccipital craniotomy. The tumor represented malignant astrocytoma. Optimal management of patients harboring sush difficult. to-treat tumors, including the role of gamma-knife radiosurgery, is discussed.