Common Brain and Spine Tumors Types
Different Types of Brain Tumors
Medulloblastoma are types of tumors that arise from undeveloped stem cells of the cerebellum, located near the middle of the back of the head. The cerebellum controls balance, posture and movement.
Medulloblastoma represents approximately 20 percent of childhood brain tumors, with the majority diagnosed before 10 years of age. It is the most common type of pediatric cancerous tumor. They can also occur in adults, although typically in younger adults aged around 20–40 years.
Gliomas represent 30% of all tumors, and some 80% of all malignant brain tumors. They are a common form of primary brain tumor in both adults and children, and arise from cells called glial cells that surround and support the neurons of the brain.
There are three types of glial cells, further distinguished as 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 sub-divisions: pilocytic astrocytoma, diffuse astrocytoma, anaplastic astrocytoma and glioblastoma multiforme. Astrocytomas account for around half of pediatric brain tumors and typically arise in the first decade of life, with the peak age at 5-8 years.
- 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 (i.e. spread) to impact another part of the body. The majority are diagnosed before the age of 10 years.
- 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, a condition that causes nerve tumors (usually benign) and skin coloration.
- Ependymoma – This type of glioma 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. Statistics show they account for around 5% of childhood nervous system tumors, and 2% of adult tumors.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, usually benign. This condition, which affects the nervous system, causes tumors to grow on nerves, as well as on and under the skin. It can either be a genetic disorder or a genetic mutation.
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.
NF1, the more common type, accounts for 90 percent of cases associated with gliomas and pheochromocytomas neurofibromatosis.
NF2 is often associated with schwannomas, 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 very 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.
Craniopharyngioma comprise around 6% of childhood brain tumors. It is usually diagnosed between the ages of 5 and 14, although they can occur at any age.
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.
Types of Spinal Tumors
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).
Clinically, spinal tumor types are divided into three major groups according to location: intramedullary, intradural-extramedullary and extradural.
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 out 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 disc 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. Breast cancer is the most common cancer to metastasize to the bone in women, and lung cancer is the most common in men, according to AANS.
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%).
Tumors Commonly Treated
- Medulloblastoma
- Gliomas
- Astrocytoma
- Brainstem Glioma
- Optic Glioma
- Ependymoma
- Neurofibromatosis
- Craniopharyngioma
- Pineal Region Tumors
- Acoustic Neuromas
- Intramedullary
- Intradural-Extramedullary
- Extradural
Causes of Hydrocephalus
Whether communicating or non-communicating, hydrocephalus can be subdivided into two different causal categories:
- Congenital
- Acquired
Speculation is that hydrocephalus may result from inherited genetic abnormalities, such as the genetic defect that causes aqueductal stenosis. One of the most common causes of hydrocephalus is “aqueductal stenosis.” In this case, hydrocephalus results from a narrowing of the aqueduct of Sylvius, a small passage between the third and fourth ventricles in the middle of the brain.
It can also be caused by developmental disorders, such as those associated with neural tube defects including spina bifida and encephalocele (in newborns, a protrusion of some or all of the brain through a defect in the skull).
Other possible causes include complications of premature birth such as intraventricular hemorrhage, and diseases such as meningitis, tumors, traumatic head injury, or subarachnoid hemorrhage, which block the exit of cerebrospinal fluid (CSF) from the ventricles to the cisterns or eliminate the passageway for CSF within the cisterns.
Congenital Hydrocephalus
Affecting one out of every 1,000 newborns, congenital hydrocephalus is the type that is present at birth. Congenital hydrocephalus is a buildup of excess cerebrospinal fluid (CSF). The extra fluid can increase pressure in the baby’s brain, which then causes brain damage and physical as well as mental problems. Discovering the condition early and treating it quickly can help limit any long-term problems. But long-term effects greatly depend on the cause of the fluid buildup, how bad it gets, and how the baby responds to treatment. Early treatment (before age 4 months) is important to help limit or prevent brain damage. However, congenital hydrocephalus is now often diagnosed before birth through a routine ultrasound. Treatment focuses on reducing the amount of fluid in the brain to relieve pressure.
Congenital hydrocephalus is caused by a complex interaction of genetic and environmental factors during fetal development. One of the most common causes of congenital hydrocephalus is “aqueductal stenosis” (a narrowing of the aqueduct of Sylvius, a cerebral aqueduct). Another common cause of hydrocephalus is a neural tube defect (NTD).
- Birth defect (such as spina bifida)
- Genetic defect
- Mother’s infections during pregnancy (such as rubella, mumps, toxoplasmosis or syphilis)
Medical problems associated with congenital hydrocephalus may include:
- Chiari malformations, an abnormality at the base of the brain where the spinal column joins the skull
- Craniosynostosis, when the bones in the skull fuse together before the brain has stopped growing
- Dandy-Walker syndrome, when the fourth ventricle is enlarged because of partial or complete closure of its outlets
- Hydranencephaly, a rare condition in which the brain’s cerebral hemispheres are absent and replaced by sacs filled with cerebrospinal fluid
- Vein of Galen aneurysmal malformations, a tangled mass of dilated vessels supplied by an enlarged artery
- Abnormal head enlargement
- Downward deviation of eyes
- Headache, irritability, nausea, sleepiness, vomiting
- Prominent scalp veins
- Skull bones may feel separated
- Tense, bulging fontanel
Acquired Hydrocephalus
Acquired hydrocephalus develops at the time of birth or at some point afterward. This type of hydrocephalus can affect individuals of all ages and may be caused by injury or disease. The following conditions may cause CSF obstruction and subsequently acquired hydrocephalus:
- Bleeding (hemorrhage)
- Brain trauma (i.e., result of injury)
- Brain tumor
- Cyst (i.e., a fluid-filled sac)
- Infection (e.g., cerebral abscess, bacterial meningitis)
Premature births may be a risk factor for hydrocephalus. Hemorrhaging, traumatic brain injury, and infection are seen in some premature births.
- Chronic headaches
- Cognitive challenges or complaints
- Difficulty walking/gait disturbances
- Urinary urgency or incontinence
Pseudotumor Cerebri
Pseudotumor cerebri (PTC) is caused by high pressure in the fluid surrounding the brain. Pseudotumor cerebri means “false brain tumor” because it mimics a tumor or hydrocephalus.
The difference between pseudotumor cerebri and hydrocephalus is that PTC fluid is encased in the extracellular space (located around each brain cell) rather than in the ventricles. In essence, then, the ventricles are compressed with PTC and expanded in the case of hydrocephalus.
PTC is often associated with overweight adolescents or sudden weight gain (such as in pregnancy). It is sometimes treated with shunting.