A brain tumor is a
mass or growth of abnormal cells in your brain. Many different types of brain
tumors exist. Some brain tumors are noncancerous (benign), and some brain
tumors are cancerous (malignant). Brain tumors can begin in your brain (primary
brain tumors), or cancer can begin in other parts of your body and spread to
your brain (secondary, or metastatic, brain tumors).
How quickly a brain
tumor grows can vary greatly. The growth rate as well as location of a brain
tumor determines how it will affect the function of your nervous system.
tumor treatment options depend on the type of brain tumor you have, as well as
its size and location.
and symptoms of a brain tumor vary greatly and depend on the brain tumor's
size, location and rate of growth.
signs and symptoms caused by brain tumors may include:
New onset or change in pattern of headaches
Headaches that gradually become more frequent and more severe
Unexplained nausea or vomiting
Vision problems, such as blurred vision, double vision or loss
of peripheral vision
Gradual loss of sensation or movement in an arm or a leg
Difficulty with balance
Confusion in everyday matters
Personality or behavior changes
Seizures, especially in someone who doesn't have a history of
Primary brain tumors
originate in the brain itself or in tissues close to it, such as in the
brain-covering membranes (meninges), cranial nerves, pituitary gland or pineal
brain tumors begin when normal cells acquire errors (mutations) in their DNA.
These mutations allow cells to grow and divide at increased rates and to
continue living when healthy cells would die. The result is a mass of abnormal
cells, which forms a tumor.
adults, primary brain tumors are much less common than are secondary brain
tumors, in which cancer begins elsewhere and spreads to the brain.
different types of primary brain tumors exist. Each gets its name from the type
of cells involved. Examples include:
Gliomas. These tumors begin in the brain or spinal cord and include
astrocytomas, ependymomas, glioblastomas, oligoastrocytomas and
Meningiomas. A meningioma is a tumor that arises from the membranes
that surround your brain and spinal cord (meninges). Most meningiomas are
Acoustic neuromas (schwannomas). These are
benign tumors that develop on the nerves that control balance and hearing
leading from your inner ear to your brain.
Pituitary adenomas. These are mostly benign tumors
that develop in the pituitary gland at the base of the brain. These tumors can
affect the pituitary hormones with effects throughout the body.
Medulloblastomas. These are the most common cancerous brain tumors in
children. A medulloblastoma starts in the lower back part of the brain and
tends to spread through the spinal fluid. These tumors are less common in
adults, but they do occur.
Germ cell tumors. Germ cell tumors may develop during childhood where the
testicles or ovaries will form. But sometimes germ cell tumors affect other
parts of the body, such as the brain.
Craniopharyngiomas. These rare, noncancerous tumors
start near the brain's pituitary gland, which secretes hormones that control
many body functions. As the craniopharyngioma slowly grows, it can affect the
pituitary gland and other structures near the brain.
In most people with primary brain tumors, the cause of the tumor is not
clear. But doctors have identified some factors that may increase your risk of
a brain tumor.
Risk factors include:
Exposure to radiation. People who
have been exposed to a type of radiation called ionizing radiation have an
increased risk of brain tumor. Examples of ionizing radiation include radiation
therapy used to treat cancer and radiation exposure caused by atomic bombs.
Family history of brain tumors. A small
portion of brain tumors occurs in people with a family history of brain tumors
or a family history of genetic syndromes that increase the risk of brain