The brain and spinal cord together constitute the central nervous system (CNS). Brain cancer is considered a rare disease. The cancer can occur in any part of the brain or spinal cord. The most common tumors are called gliomas (astrocytoma, anaplastic astrocytoma, or glioblastoma multiforme). Other tumor types include: Oligodendroglioma, Ependymoma, Meningioma, Lymphoma, Schwannoma, and Medulloblastoma.