OLIGODENDROGLIOMA - May be subdivided into primary brain tumors and the more common, secondary brain tumors. Primary brain tumors (e.g. astrocytoma, craniopharyngioma, glioma, ependymoma, neuroglioma, oligodendroglioma, glioblastoma multiforme, meningioma, and medulloblastoma) arise from the uncontrolled proliferation of cells within the brain. Secondary brain tumors occur from the spread of cancer into the brain from a distant cancerous organ (metastasis). Common symptoms of a brain tumor include headache, nausea, vomiting, seizures, change in mentation, neurologic symptoms and loss of memory.