Gliomas are a common primary brain tumor that arise from cells called glial cells that surround and support the neurons of the brain. There are three types of glial cells: astrocytes, oligodendrocytes, and ependymal cells.
- Astrocytoma – These tumors, the most common form of gliomas, are in glial cells called astrocytes -star-shaped cells in the brain and spinal cord that support neurons and help remove debris. They are usually slow-growing tumors that cause swelling particularly in the area behind the eyes. Astrocytomas include a variety of subdivisions: pilocytic astrocytoma, diffuse astrocytoma, anaplastic astrocytoma and glioblastoma multiforme.
- Brainstem Glioma – Originating in the brain or spinal cord tissue, these tumors typically spread throughout the nervous system. Brainstem gliomas are often primary brain tumors, and rarely metastasize (or spread) to impact another part of the body.
- Optic Glioma – These types of tumors can occur on one or both of the optic nerves, or on the area of the hypothalamus where the optic nerves cross each other (optic chiasm). Optic gliomas are slow-growing, usually benign and are often associated with Type 1 Neurofibromatosis.
- Ependymoma – This is a type of glioma that originates from tissue of the central nervous system called the ependyma. Ependymomas are made up of malignant cancer cells which, in the pediatric variety, form in the brain and the spinal cord. Classified as either supratentorial (in the top part of the head) or infratentorial (in the back of the head), the majority of pediatric ependymomas occur as infratentorial tumors located in or around the fluid-filled fourth cranial ventricle. Ependymomas may are also be associated with Type 2 Neurofibromatosis.
Neurofibromatosis is a syndrome of an abnormality in a gene that leads to tumors. The condition, which affects the nervous system, causes tumors to grow on nerves. It can either be a genetic disorder or a genetic mutation. The tumors are usually benign and grow on nerves, as well as on and under the skin. Type 1 Neurofibromatosis (NF1), which can present symptoms as early as at birth, can affect the skin, bones and brain. Type 2 Neurofibromatosis (NF2) frequently starts in the teenage years and causes poor balance, ringing in the ears and hearing loss. Gliomas and pheochromocytomas neurofibromatosis is associated with NF1 and NF2 is associated with schwannoma, meningiomas, and ependymomas.
A craniopharyngioma is a benign tumor that develops near the pituitary gland (a small endocrine gland at the base of the brain). Craniopharyngiomas are typically slow-growing tumors. At ANA, we use a relatively new, innovative and less invasive surgical approach called the endonasal endoscopy to treat these types of tumors.
Pineal region tumors
The pineal gland is a small gland located in the back of the base of the brain. Although its purpose is not entirely understood, it is known to create the hormones melatonin and serotonin. The most common type of these tumors in this region are germ cell tumors, which arise from developmental abnormalities, and pineal cell tumors, which arise from normal cells of the pineal gland itself.
Spinal tumors are often referred to by the area of the spine in which they occur. These basic areas are cervical, thoracic, lumbar and sacrum. Additionally, they also are classified by their location in the spine – anterior (front) and posterior (back).
Intramedullary tumors grow inside the spinal cord or on the individual nerves, most frequently occurring in the cervical (neck) region. They typically derive from glial or ependymal cells that are found throughout the interstitium of the cord. Astrocytomas and ependymomas are the two most common types, often benign, but can be difficult to remove. Intramedullary lipomas are rare congenital tumors most commonly located in the thoracic spinal cord.
Intradural-extramedullary tumors can develop in the spinal cord’s arachnoid membrane (meningiomas), in the nerve roots that extend from the spinal cord (schwannomas and neurofibromas) or at the spinal cord base (filum terminale ependymomas). Although meningiomas are often benign, they can be difficult to remove and may recur. Nerve root tumors are also generally benign, although neurofibromas may become malignant over time. Ependymomas at the end of the spinal cord can be large, and the delicate nature of fine neural structures in that area may complicate treatment.
Extradural tumors occur in the vertebral column, and grow either from the bone or disk elements of the spine. These lesions are typically attributed to metastatic cancer or schwannomas derived from the cells covering the nerve roots. Occasionally, an extradural tumor extends through the intervertebral foramina, lying partially within and partially outside of the spinal canal. The spinal column is the most common site for bone metastasis.
Research indicates that 30% to 90% of patients with cancer will experience the spread of cancer to their spine. Common primary cancers that spread to the spine are lung, breast and prostate. Lung cancer is the most common cancer to metastasize to the bone in men, and breast cancer is the most common in women. Other cancers that spread to the spine include lymphoma, melanoma and sarcoma, as well as cancers of the gastrointestinal tract, kidney and thyroid. Nearly 5% to 10% of patients with systemic cancer suffer spinal metastases, and approximately 30% to 70% of patients with solid tumors have spinal metastatic disease. Breast, lung, prostate, andrenal cell carcinomas; lymphoma; and sarcoma account for 70% of all sources of spinal metastasis. The metastases occur in the vertebral body (60%), posterior elements (30%), or both (10%).