Glioma

Treatment

Treatment of gliomas is a team process at Mayo Clinic. Specialists from the brain tumor treatment team work together to provide the high-quality, integrated model of care for which Mayo Clinic is known. A neurologist who has expertise and additional training in neuro-oncology usually serves as the primary physician, who helps to coordinate overall care with a team consisting of neurosurgery, medical oncology, radiation oncology, neuropathology and neuroradiology specialists.

New glioma treatments are developed continually, so several options may be available for patients. The pros and cons of each option are discussed in detail during treatment planning. Mayo Clinic's goal is to improve both the duration and quality of survival. Every effort is made to tailor the treatment program to the needs of each patient and family.

Treatment options and survival odds depend on the glioma type, size and location, as well as the patient's age and overall health. For treatment specifics, see descriptions of each glioma type:

• Astrocytomas
• Ependymomas
• Glioblastoma multiforme
• Oligodendrogliomas
• Mixed gliomas

Once treated, a glioma may remain in remission, although the duration of the remission is variable. In remission, the glioma cells have stopped growing or multiplying. If or when the tumor grows back, the team is again assembled to comprehensively reevaluate the patient and to review all treatment options. In some patients, the glioma may never recur. During follow-up visits, patients are usually monitored regularly for glioma recurrence with MRI or CT scans.

Quality of Life

Mayo Clinic physicians pay particular attention to the patient's quality of life as they aggressively seek to eradicate gliomas. As glioma treatment becomes more successful, patients live longer but also face greater risks of long-term adverse effects of treatment. The most significant adverse effects are cognitive problems. Mayo specialists, including neuropsychologists and experts in brain rehabilitation, help patients with these issues. Almost all clinical trials at Mayo Clinic and the North Central Cancer Treatment Group incorporate quality-of-life measures.

Whenever possible, the glioma treatment team integrates care from the patient's local physician and oncologists to offer the most comprehensive treatment program management. Mayo specialists work with local physicians to administer some therapy close to home for patients who live a significant distance from Mayo Clinic.

3-D computer-generated brain model

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Treatment Options

Surgery
Surgery is the initial therapy for nearly all patients with gliomas. It can cure most benign gliomas, as well as meningiomas. The goal of surgery is to remove as much of the glioma as possible while minimizing damage to healthy tissue.

Some gliomas can be removed completely; others can be removed only partially or not at all. Partial removal helps relieve symptoms by reducing pressure on the brain and reducing the size of the glioma to be treated by radiation or chemotherapy.

After the glioma has been removed, Mayo Clinic pathologists immediately evaluate the tissue and report results directly to the surgeon in the operating room. Direct, face-to-face contact with the pathologist during the surgery allows the surgeon to verify that the glioma has been fully removed and may reduce the need for an additional operation.

If a glioma cannot be surgically removed, the physician may do only a biopsy. A small piece of the glioma is removed so a pathologist can examine it under a microscope to determine its cell makeup. The finding helps determine the proper treatment.

Patients diagnosed with brain gliomas often can be scheduled for surgery the next day, if desired. Surgeons provide patients with information to help them decide which treatment is best for them. Surgical removal demands great skill. Mayo's neurosurgeons operate on hundreds of patients each year, using the latest technological advances. Mayo surgeons were pioneers in developing computer-assisted neurosurgery, which allows surgeons to precisely map the brain and more accurately and aggressively treat brain tumors.

Another technology available at Mayo Clinic is intraoperative MRI, which provides the neurosurgeon with real-time data on glioma size and location.

Mayo Clinic neurosurgeons also use awake brain surgery on gliomas that infiltrate brain regions which control functions such as speech and movement. The surgery is performed with the patient awake during segments of the operation. The patient's responses to questions allow the surgeon and attending team to more precisely identify critical brain regions and minimize injury during glioma removal.

Radiation Therapy
Radiation Therapy is an essential component of treatment for many patients with gliomas. It can be curative some patients and prolongs survival for most.

The traditional form of radiation therapy, referred to as fractionated radiation, delivers radiation in small doses (fractions). Typically, patients are treated once daily, five times per week, for a total of five to six weeks. Even after the tumor visible on the CT or MRI scan is removed, radiation is often used to treat the margin of brain around the surgical cavity, going after the microscopic tumor cells that have infiltrated the area from the original mass.

External Beam Radiation
This traditional form of radiation therapy delivers radiation from outside the body. The radiation usually involves treatments five days a week. The length of treatment time depends on the type of glioma. External beam radiation is less precise than Fractionalized Stereotactic Radiotherapy, but allows a wider area of tissue around the glioma to be treated.

Fractionalized Stereotactic Radiotherapy (FSR)
Fractionalized Stereotactic Radiotherapy minimizes damage to healthy tissue by carefully targeting radiation. FSR involves many small treatments instead of one big dose of radiation. Healthy brain tissues and cranial nerves that cannot tolerate a single, large treatment can tolerate many small treatments.

This treatment also offers the biological benefit of fractionation (separation into different portions) to exploit the different sensitivities of healthy versus cancerous tissue. These advantages are helpful when treating lesions near delicate structures such as the optic nerves, which cannot tolerate high levels of radiation.

For FSR, the glioma patient is fitted with a plastic mask that helps locate the glioma and target the radiation during treatment. The patient lies on a table. X-rays are taken to determine correct positioning. The treatment is given in several small units called arcs. The number of treatments depends on the size and location of the glioma.

Gamma Knife
Machine™

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Stereotactic Radiosurgery
Stereotactic Radiosurgery is effective for lesions such as meningioma or small brain metastases that are confined to a limited area. It spares nearby healthy tissue because radiation levels drop rapidly at the edges of the area being treated.

Radiosurgery is not typically used in the treatment of gliomas. Gliomas tend to be infiltrative tumors, so the areas around the surgical cavity or around the visible tumor mass are not ideal targets for radiosurgery. Fractionated radiation is used most often.

Chemotherapy
Chemotherapy is an important part of the care of glioma patients. For patients with glioblastoma (Grade 4 astroccytoma), the most rapidly growing and aggressive glioma, the addition of chemotherapy to the radiation has been shown to significantly extend a patient's lifespan. Current research is focused on the development and evaluation of new drugs to use with radiation for a newly diagnosed tumor, as well as for recurrent gliomas.

Mayo Clinic is a research leader in treating brain tumors with chemotherapy, and patients may be offered an opportunity to participate in trials that are appropriate for their situation.

Molecular Targeted Therapy
Advances in the understanding of the cellular mechanisms involved in growth and progression of brain tumors has allowed the development of new drugs that block receptors on the tumor cell surfaces, affect intracellular chemical pathways (signaling pathways) or interact with proteins or DNA in the tumor cell nuclei.

Mayo Clinic researchers have been integrally involved in testing these agents in brain tumor patients. Mayo has participated in several clinical trials within the North Central Cancer Treatment Group involving administration of targeted therapies in patients with both newly diagnosed and recurrent brain tumors.

Other Drugs
Corticosteroids are indispensable for reducing the size of gliomas and controlling increased intracranial pressure. The long-term use of these agents, however, can result in substantial toxic effects.

Anti-seizure drugs are also important in the care of patients who experience seizures.

Deep vein thrombosis or pulmonary emboli can occur in 20 percent to 30 percent of patients with primary brain tumors. Conventional therapy with heparin and warfarin is usually effective and well-tolerated.

Vaccine and Viral Therapies
Modulation of the patient's immune system to attempt to control the glioma by immunization or induction of immune cells and the use of modified viruses to attack the tumor are other treatment approaches studied at Mayo Clinic. Clinical trials with vaccines and virus therapy are underway.

Combination Treatments
Many gliomas are treated with a combination of surgery, radiation, chemotherapy or molecular targeted agents.

Clinical Trials
Mayo Clinic participates in many clinical trials for brain and nervous system gliomas, including trials originating at Mayo Clinic and those sponsored by the National Cancer Institute through the North Central Cancer Treatment Group.

Brain Rehabilitation
Brain injury can lead to problems with thoughts, feelings and behaviors. Many people with brain injury find that returning to independent living, work or school presents challenges with which they need assistance. Mayo Clinic rehabilitation specialists help people with brain injury live as independently as possible within their family and community. Depression is also common in brain tumor patients. Clinical trials are being conducted to investigate the use of antidepressants to improve the quality of life for these patients.