The central nervous system consists of the brain and spine. They control your thought processing and bodily functions such as speech, memory, understanding (cognition), motor skills, coordination and balance. Because the brain and spine control such important functions, tumors in these areas can be particularly challenging but necessary to treat. Brain and spine tumor specialists have to remove tumors surgically or treat the tumor with radiation and/or drug therapy without disrupting essential functions.

Approximately 400,000 people are diagnosed with a brain or spine tumor in the U.S. every year. Tumors can grow in many different locations within the brain and spine, and each person’s anatomy is a little different, requiring treatment to be highly personalized to accommodate unique aspects. Most of these tumors are cancers that have spread to the brain or spine from other parts of the body (metastases). The majority of neurological tumors are malignant, but some are benign.

Learn More About Spine Tumors

Primary Brain Tumors

A primary brain tumor is a tumor that begins in the brain rather than a malignancy that spreads to the brain from another part of the body. Tumors that spread to the brain are called metastases. Imaging can suggest the type of primary brain tumor but ultimately, it is the results of pathology (tests and analysis of tumor tissue removed during surgery) that confirms the type of brain tumor and its grade. Confirming this information requires the expertise of a neuro-pathologist.

Tumors at the base of the skull require special skills and expertise, as they involve the brain stem and other vital areas of the brain. Learn more about the expert neurosurgeons in our Skull Base Tumor Program. We offer innovative treatment approaches that only a few doctors in the U.S. perform.

Causes of Primary Brain Tumors

Most primary brain tumors have no known cause. Researchers have studied a wide variety of possible risk factors, including diet, occupational hazards, prior head injury — even water supply — but none has ever been established as a cause of primary brain tumors. Your tumor is not the result of anything you did or did not do.

Only very rarely is a personal risk of brain tumor passed on genetically. Your children and grandchildren are not at a heightened genetic risk of a neurological cancer. Unless they are experiencing symptoms of a neurological tumor, there is no need for anyone in your family to see a doctor or have a brain scan.

The only known cause is radiation therapy. The most common scenario is a young adult who had radiation therapy as a child for another cancer. Decades later, it is possible to develop a brain tumor but that is also extremely rare.


Gliomas are the most common type of primary brain tumors. They are divided into subsets:

  • Astrocytomas are graded on four levels with grade 1 being most common among children (pediatric population).
    • Grade 1 astrocytomas are contained rather than spread across a wide area and can often be cured with surgery alone.
    • Grade 2 astrocytomas are low-grade tumors also known as diffuse (spread across a wide area) gliomas that typically grow slowly but have the potential to transform into more aggressive tumors, including grade 3 and grade 4 astrocytomas.
    • Grade 3 astrocytomas, also known as anaplastic astrocytomas, are malignant gliomas that grow more quickly.
    • Grade 4 astrocytomas, also known as glioblastoma multiforme or GBM, are malignant gliomas and are the most aggressive primary brain tumors.
  • Oligodendrogliomas are either grade 2 or grade 3, and although they can develop in any part of the central nervous system, they are usually found in the white matter and outer layer of the brain — the cortex. They develop more often in men than women and typically between the ages of 35 and 44. If there are symptoms, they depend on the tumor’s location.
    • Grade 2 oligodendrogeliomas are low-grade and grow slowly, but they do invade nearby brain tissues. They may form years before diagnosis without symptoms to indicate their presence.
    • Grade 3 oligodendroegliomas, also known as anaplastic oligodendriogeliomas, are malignant (cancer), and they are fast-growing.

Gliomas typically cause symptoms with a rapid onset — from the tumor itself or from fluid around the tumor that causes swelling in the brain. Brain tumor symptoms can include the following.

  • Seizures that you have not had before.
  • Severe and debilitating headaches that persist despite over-the-counter pain relievers
  • Nausea and vomiting brought on by headache severity 
  • Disturbances in vision
  • Changes in personality or cognition — how you think and your memory
  • Focal neurologic deficits (paralysis, change in muscle tone, weakness or involuntary movements).


Meningiomas get their name from the area where they start — the layers of tissue that cover the brain and the spinal cord, which are called the meninges. Most meningiomas are benign. They grow slowly and are far more common than gliomas, representing about 36% of primary brain tumors. They happen more than twice as often with women as with men, which may indicate a link to the female hormone progesterone. They often grow inward, causing pressure in the brain, rather than invading the brain, and they can affect the spinal cord.

Most people who have meningiomas do not need anything more than other than ongoing surveillance. However, in cases of large meningiomas, growing meningiomas or symptomatic meningiomas, treatment is recommended. Surgery or radiation therapy are considered first line treatments in these cases with the goal of extending your survival with the best quality of life.

Additionally, research is being conducted to better understand how brain tumors change the way your brain is wired, known as neuroplasticity. We are examining ways to induce adaptations in the brain’s motor cortex. We hope this will one day enable us to perform complete resections of such lesions while protecting critical functions. We have teamed up with a leading device manufacturer to help us develop these techniques. Learn more about this brain tumor research.

Pituitary Tumors

The large majority of pituitary tumors are benign. Problems arise when cancerous cells within the pituitary produce an excess of hormones such as growth hormones or prolactin, which can lead to multiple health problems. In addition, very large pituitary tumors (which often do not secrete hormones) can compress surrounding brain structures and nerve tissue, causing loss of peripheral vision and other neurological problems. Most pituitary tumors can be managed with minimally invasive procedures. Learn more about pituitary tumor treatment

Brain Tumor Research and Tissue Neuro-Oncology Brain Bank

To study the molecular and genetic makeup of brain tumors, as well as their appearance on imaging, researchers at the Medical College of Wisconsin have established a tissue bank. A patient interested in participating can donate brain tissue samples from surgery or include plans to donate their entire brain for study as part of their legacy. This valuable resource helps our researchers learn about these tumors and help our brain tumor team better anticipate the disease process. Patients or families interested in this ongoing research project can contact their neuro-oncologist for additional information.

Brain Metastases Treatment if Your Cancer Spreads

If your cancer spreads, or metastasizes, to the brain from cancer that originates in another part of your body — an occurrence that is about 10% more common than cancers that start in the brain — the Brain and Spine Tumor Program has a team designed to care for your complex needs. The Brain Metastases Program offers specialized expertise that is vital for successful treatment because there are many nuances in medical decision-making and for personalizing treatment for each individual.

This program supports not only patients, but also their physicians who may need to refer them for brain metastasis care. A virtual network is available through an app called NIMBLE (Network for Integrated Management of Brain Metastasis Linking Experts) provides these physicians with a multidisciplinary, real-time virtual tumor board. Physicians can receive comprehensive treatment recommendations in hours rather than days.

Learn More About BrainMets

Neuro-Oncology Cognitive Clinic 

Patients with brain tumors can experience changes in thinking, memory, emotions and other cognitive abilities. As part of our dedication to preserving quality of life, the Brain and Spine Tumor Program includes a neuropsychologist who monitors these changes and helps you adjust. Learn more about the Neuro-Oncology Cognitive Clinic.

Get a Second Opinion for Brain Cancer

A second opinion can provide you with peace of mind in knowing that your diagnosis is accurate and that you have explored all treatment options available to you, including clinical trials. Our new patient coordinator will help ease your way by gathering your medical records and scheduling tests and appointments. Learn more about our Cancer Second Opinion Program, which includes virtual as well as in-person options.

Tumor Board: Coordinated Cancer Care

The entire Brain and Spine Tumor Program team meets every week to discuss patients and monitor results. During these tumor board meetings, neurosurgeons, neuro-oncologists, radiation oncologists, neuroradiologists, neuropathologists, neuropsychologists, researchers and others use their collective expertise to develop individualized treatment plans for patients with brain and spine tumors.

Group evaluation and planning is especially important for patients with recurring cancer. Sophisticated image-guidance such as advanced magnetic resonance imaging (MRI) guides our diagnostics, some treatments and monitoring of your progress. Our multidisciplinary approach ensures that every treatment option is considered for every patient, including any available clinical trials.

The Froedtert & MCW Skull Base Program has been designated as a North American Skull Base Society (NASBS) 2021 Multidisciplinary Team of Distinction. The NASBS strives to create an inclusive focus for the society's educational offerings, programs and members by welcoming a wide variety of health care professionals who provide skull base patient care. In keeping with that approach, they recognize member institutions that have multidisciplinary skull base surgery teams that include physicians in a variety of specialties.

Virtual Visits Are Available

Safe and convenient virtual visits by video let you get the care you need via a mobile device, tablet or computer wherever you are. We’ll gather your medical records for you and get our experts’ input so we can offer treatment options without an in-person visit. To schedule a virtual visit, call 1-866-680-0505.