Brain Tumor

What is a brain tumor?

Normal cells grow in a controlled manner as new cells replace old or damaged ones. For reasons not fully understood, tumor cells reproduce uncontrollably. 

A primary brain tumor is an abnormal growth that starts in the brain and usually does not spread to other parts of the body. Primary brain tumors may be benign or malignant. A benign brain tumor grows slowly, has distinct boundaries, and rarely spreads. Although its cells are not malignant, benign tumors can be life threatening if located in a vital area. A malignant brain tumor grows quickly, has irregular boundaries, and spreads to nearby brain areas. Although they are often called brain cancer, malignant brain tumors do not fit the definition of cancer because they do not spread to organs outside the brain and spine.

Metastatic (secondary) brain tumors begin as cancer elsewhere in the body and spread to the brain. They form when cancer cells are carried in the blood stream. The most common cancers that spread to the brain are lung and breast.

Whether a brain tumor is benign, malignant, or metastatic, all are potentially life-threatening. Enclosed within the bony skull, the brain cannot expand to make room for a growing mass. As a result, the tumor compresses and displaces normal brain tissue. 

Types of brain tumors

There are over 120 different types of brain tumors. Common brain tumors include:

• Gliomas
• Craniopharyngioma
• Epidermoid
• Lymphoma
• Meningioma
• Schwannoma (neuroma)
• Pituitary adenoma
• Pinealoma (pineocytoma, pineoblastoma)
• Medulloblastoma

The World Health Organization (WHO) developed a classification and grading system to standardize communication, treatment planning, and predict outcomes for brain tumors. Tumors area classified by their cell type and grade by viewing the cells, usually taken during biopsy, under a microscope.

• Cell type. Refers to the cell of origin of the tumor.
• Grade. Refers to the way tumor cells look under the microscope and is an indication of aggressiveness.

What causes brain tumors?

Medical science neither knows what causes brain tumors nor how to prevent primary tumors that start in the brain. People most at risk for brain tumors include those who have:

• Cancer elsewhere in the body
• Prolonged exposure to pesticides, industrial solvents, and other chemicals
• Inherited diseases, such as neurofibromatosis

Brain tumor symptoms

Symptoms vary depending on the tumor’s type, size, and location in the brain. General symptoms include:

• Headaches that tend to worsen in the morning
• Seizures
• Stumbling, dizziness, difficulty walking
• Speech problems (e.g., difficulty finding the right word)
• Vision problems, abnormal eye movements
• Weakness on one side of the body
• Increased intracranial pressure, which causes drowsiness, headaches, nausea and vomiting, sluggish responses

Who is affected?

Metastatic (secondary) brain tumors are five times more common than primary brain tumors and they occur in 10% to 30% of cancer patients. People are surviving cancer longer than ever before. As a result, metastatic brain tumors will likely increase in the years to come. Although brain tumors can occur at any age, they are most common in children 3 to 12 years old and in adults 40 to 70 years old.

How is a diagnosis made?

First, the doctor will obtain your personal and family medical history and perform a complete physical exam. In addition to checking your general health, the doctor performs a neurological exam to check mental status and memory, cranial nerve function (sight, hearing, smell, tongue and facial movement), muscle strength, coordination, reflexes, and response to pain. Additional tests may include:

• Audiometry, a hearing test performed by an audiologist, detects hearing loss due to tumors near the cochlear nerve (e.g., acoustic neuroma).
• An endocrine evaluation measures hormone levels in your blood or urine to detect abnormal levels caused by pituitary tumors (e.g., Cushing’s Disease).
• A visual field acuity test is performed by a neuro-ophthalmologist to detect vision loss and missing areas in your field of view.
• A lumbar puncture (spinal tap) may be performed to examine cerebrospinal fluid for tumor cells, proteins, infection, and blood.
• CT Scan
• MRI
• Biopsy

Brain tumor treatment options

Treatment options vary depending on the tumor type, grade, size and location; whether it has spread; and your age and general health. The goal of treatment may be curative or focus on relieving symptoms (palliative care). Treatment are often used in combination with one another. The goal is to remove all or as much of the tumor as possible through surgery to minimize the chance of recurrence. Radiation therapy and chemotherapy are used to treat tumors that cannot be removed by surgery alone. For example, surgery may remove the bulk of the tumor and a small amount of residual tumor near a critical structure can later be treated with radiation.

• Observation - Sometimes the best treatment is observation. For example, benign, slow growing tumors that are small and have few symptoms may be observed with routine MRI scans every year until their growth or symptoms necessitate surgery. Observation may be the best option for people who are older or with other health conditions.
• Surgery – Surgery is the treatment of choice for brain tumors that can be reached without causing major injury to vital parts of the brain. Surgery can help to refine the diagnosis, remove as much of the tumor as possible, and release pressure within the skull. A neurosurgeon performs a craniotomy to open the skull and remove the tumor. Sometimes only part of the tumor is removed if it is near critical areas of the brain. A partial removal can still relieve symptoms. Radiation or chemotherapy may be used on the remaining tumor cells.
• Laser Interstitial Thermal Therapy – A minimally invasive treatment that transmits heat to “cook” brain tumors from the inside out.
• Radiation – Controlled, high-energy rays to treat brain tumors. Radiation damages the DNA inside cells, making them unable to divide and grow. Aggressive tumors, whose cells divide rapidly, tend to respond quickly to radiation. Over time, the abnormal cells die and the tumor may shrink.
• Chemotherapy – Chemotherapy drugs disrupt cell division. Over time, chemo causes the abnormal cells to die and the tumor may shrink. This treatment can damage normal cells, but they can repair themselves better than abnormal cells. Treatment is delivered in cycles with rest periods in between to allow the body to rebuild healthy cells.
• Immunotherapy – Also known as biotherapy, activates the immune system (T-cells and antibodies) to destroy tumor cells. Research is exploring ways to prevent or treat cancer through vaccines.
• Gene therapy – Uses viruses or other vectors to introduce new genetic materials into tumor cells. This experimental therapy can cause tumor cells to die or increase their susceptibility to other cancer therapies.
• Hyperbaric oxygen – Using oxygen at higher-than-normal levels to promote wound healing and help fight infection. It may also improve the tumor’s responsiveness to radiation. Currently it is being used to help the body naturally remove dead tumor cells and treat radiation necrosis.
• Tumor Treating Fields (TTFields) – Slows and reserves tumor growth by preventing cells from dividing. Treatment involves wearing a device resembling a bathing cap that delivers electromagnetic energy to the scalp. Patients wear the device all the time.
• Clinical trials – Research studies in which new treatments – drugs, diagnostics, procedures, and other therapies – are tested in people to see if they’re safe and effective. Research is always being conducted to improve the standard of medical care. Information about current clinical trials, including eligibility, protocol, and locations, are found on the web. Studies can be sponsored by the National Institute of Health (see clinicaltrials.gov) as well as private industry and pharmaceutical companies (see www.centerwatch.com).

Recovery and prevention

Your primary care doctor and oncologist should discuss any home care needs with you and your family. Supportive measures vary according to your symptoms. 

Driving privileges may be suspended while you are taking anti-seizure medication. As each state has different rules about driving and seizures, discuss the issue with your doctor.

It may also be appropriate to discuss advance medical directives (e.g., living will, health care proxy, durable power of attorney) with your family to ensure your medical care and wishes are followed.

Rehabilitation

Because brain tumors develop in parts of the brain that control movement, speech, vision and thinking, rehabilitation may be a necessary part of recovery. Although the brain can sometimes heal itself after the trauma of treatment, it will take time and patience. A neuropsychologist can help patients evaluate changes caused by their brain tumor and develop a plan for rehabilitation. 

Recurrence

How well a tumor will respond to treatment, remain in remission, or recur after treatment depends on the specific tumor type and location. A current tumor may be a tumor that still persists after treatment, one that grows back some time after treatment destroyed it, or a new tumor that grows in the same place as the original one.

When a brain tumor is in remission, the tumor cells have stopped growing or multiplying. Periods of remission vary. In general, benign tumors recur less often than malignant ones.

Since it is impossible to predict whether or when a particular tumor may recur, lifelong monitoring with MRI or CT scans is essential for people treated for a brain tumor, even a benign lesion. Follow-up scans may be performed every 3 to 6 months or annually, depending on the type of tumor you had.

If you have any questions or would like to schedule an appointment with on of our Spine Center specialists, please call 515.875.9560.

Support groups provide an opportunity for patients and their families to share experiences, receive support, and learn about advances in treatments and medications.

American Brain Tumor Association – www.abta.org – 1.800.886.2282

National Brain Tumor Society – www.braintumor.org – 1.800.934.2873

National Cancer Institute – www.cancer.gov