<unk> s, or<unk> s, are vascular tumors of the central nervous system that originate from the vascular system, usually during middle age. Sometimes, these tumors occur in other sites such as the spinal cord and retina. They may be associated with other diseases such as polycythemia (increased blood cell count), pancreatic cysts and Von Hippel–Lindau syndrome (VHL syndrome).<unk> s are most commonly composed of stromal cells in small blood vessels and usually occur in the cerebellum, brainstem or spinal cord. They are classed as grade I tumors under the World Health Organization's classification system.
Hemangioblastoma
Ameloblastoma
Medulloblastoma
Glioblastoma
Hemangiopericytoma
Neuroma
Glioma
Sialoblastoma