The information on this page was reviewed and approved by
Maurie Markman, MD, President, Medicine & Science at CTCA.
This page was updated on April 2, 2021.
Primary brain tumors, which form from cells within the brain, may be malignant (cancerous) or benign (non-cancerous). However, even benign tumors can damage normal brain tissue and cause serious problems.
Benign tumors grow slowly and tend to be more amenable to surgical or other treatments. Malignant brain tumors are more aggressive and grow faster.
When cancer develops elsewhere in the body and spreads to the brain, it’s called a secondary brain tumor, or brain metastasis. Lung cancer, colon cancer, kidney cancer and breast cancer can all metastasize to the brain. These tumors are more common than primary brain tumors.
Brain cancer cells may travel short distances within the brain, but they generally do not spread beyond the brain. The chance of developing a malignant brain or spinal cord tumor is less than 1 percent. Men are at a slightly higher risk—about one in 140—while women have a one in 190 chance of getting this cancer type, although women are at a greater risk for certain types of brain tumors.
There is no definitive cause of brain tumors or brain cancer. The risk of developing primary brain cancer is very low. The American Cancer Society estimates the risk over a lifetime at less than 1 percent.
While risk factors for brain cancer are much less defined than for other cancers, some genetic conditions and environmental factors may contribute to the development of the disease. Those risk factors include:
The frequency of brain cancer increases with age, with more cases in individuals aged 65 and older. The age factor varies depending on the cell type and location of the tumor.
Certain cancers, like meningiomas, are twice as likely to develop in women, while medulloblastomas—predominantly diagnosed in children—are more frequently found in males.
Although not conclusive, cancer research indicates that chemical exposure may lead to a higher incidence of some brain tumors in individuals who work in oil refining, rubber manufacturing and drug manufacturing.
There are more than 120 types of brain tumors, according to the National Brain Tumor Society. Some brain tumors, such as a glioblastoma multiforme, are malignant and may be fast-growing. Other types of brain tumors, such as meningiomas and schwannomas, may be slow-growing and benign.
The most common type of primary brain tumor is called a glioma, which originates in the glial (supportive) tissue. About one-third of all primary brain tumors and other nervous system tumors form from this type of cell.
The types of brain tumors include:
Symptoms of brain cancer are influenced by which parts of the brain are involved and the functional systems affected. For example, vision problems may result from a tumor near the optic nerve. A tumor in the front part of the brain may affect the ability to concentrate and think. A tumor located in an area that controls motor function may cause weakness, numbness or difficulty with speech.
Signs of brain cancer may include:
Some patients may experience cognitive impairments or they may have visual, speech or coordination problems. Symptoms may be subtle or develop gradually.
It’s important to understand that even noncancerous tumors often damage normal cells in the surrounding brain tissue, nerves and blood vessels. This can cause side effects, such as headaches, fatigue, double-vision or blurred vision.
Health care professionals use the following tools to diagnose brain cancer:
Treatment options for brain cancer patients include:
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