A brain tumor is a mass of abnormal cells in the brain. There are many different types of brain tumors, and they can be either benign (noncancerous) or malignant (cancerous). Brain tumors can be divided into two broad categories: primary and secondary (metastatic).
Primary Brain Tumors
These tumors originate in the brain itself or in tissues near it, such as membranes that cover the brain (meninges), cranial nerves, the pituitary gland, and the pineal gland. They form when mutations occur in the DNA of normal cells, causing the cells to multiply abnormally and survive in conditions that normal cells would not.
Many different types of primary brain tumors exist, and they are usually named after the type of cells they are thought to originate from:
- Acoustic neuromas (vestibular schwannomas)
- Germ cell tumors
- Gliomas (including glioblastomas, gliosarcomas, astrocytomas, oligodendrogliomas, and oligoastrocytomas)
- Medulloblastomas (including primitive neuroectodermal tumors, or PNETs)
- Pineal-region tumors (including pineocytomas and pineoblastomas)
- Pituitary tumors (including pituitary adenomas)
Secondary (Metastatic) Brain Tumors
These tumors spread to the brain from other cancerous sites in the body. They occur most often in people with a known history of cancer, but a metastatic brain tumor may be the first sign of cancer that began somewhere else in the body.
Any cancer can spread to the brain, but the types of cancer most likely to do so are:
- Breast cancer
- Colon cancer
- Lung cancer
- Kidney cancer
How common are brain tumors?
Nearly 700,000 people in the U.S. are living with a brain tumor. Metastatic brain tumors are much more common than primary brain tumors.
In most cases, it is not known what causes the genetic mutations that lead to primary brain tumors. However, some risk factors have been identified:
- Older age
- Family history of brain tumors
- Exposure to ionizing radiation
- A depressed immune system due to a disease or certain medication
Who gets brain tumors?
A brain tumor can occur in any person at any age. Primary brain tumors are more common in children and older adults. Metastatic brain tumors are more common in adults than in children.
How are brain tumors diagnosed?
The following tests may be used to diagnose a brain tumor and determine its type:
- Neurological exam
- CT scan
- MRI scan
Brain tumor symptoms vary widely depending on the type, location, size, and growth rate of the tumor. There are no specific symptoms that only occur due to a brain tumor.
General symptoms of brain tumors include:
- New onset or change in pattern of headaches
- Headaches that gradually become more frequent and more severe
- New onset of seizures
- Gradual loss of sensation or movement in an arm or a leg
- Difficulty with balance
- Difficulty speaking
- Personality or behavior changes
- Unexplained nausea or vomiting
- Blurred vision, double vision, or loss of peripheral vision
- Hearing problems
Contact a medical professional if you are experiencing any symptoms.
Treatment for a brain tumor depends on its type, size, location, and growth rate, as well as your overall health. A combination of treatments may be used.
Treatment options include:
- Radiation therapy
- Radiosurgery, such as Gamma Knife or Cyber Knife, which are offered here at Barrow Neurological Institute at Dignity Health St. Joseph’s Hospital and Medical Center
Following treatment, neuro-rehabilitation may be necessary if the tumor affected regions of the brain that control motor skills, speech, vision, or thinking.
- Date of last review: June 20, 2019
- Author: Nader Sanai, MD