Glioma treatment

Last updated Dec. 20, 2024, by Lindsey Shapiro, PhD
Fact-checked by Ana de Barros, PhD

Treatment approach

Tumor treating fields

Treatment for gliomas, a diverse group of tumors that form in the brain and spinal cord, can involve a variety of approaches, including surgery, radiation therapy, and chemotherapy, as well as a range of supportive treatments.

Glioma treatment can be complicated, as the tumor often grows into nearby healthy tissue that’s critical for normal brain function. Doctors usually consider the type of tumor, its location, and how aggressive it is, as well as other individual factors, to determine the best treatment options for each case.

While surgery to remove the cancer is typically the first approach, it’s generally only curative for slow-growing tumors. For those with more aggressive gliomas, surgery can be combined with other treatments to help ease symptoms and extend survival.

Understanding glioma treatment

Gliomas are tumors that form in glia, a group of cells that support the health of the nerve cells in the brain and spinal cord. They’re classified into three main types based on the specific cells they originate in:

astrocytomas, which arise in astrocytes
oligodendrogliomas, which start in oligodendrocytes
ependymomas, which begin in ependymocytes.

Gliomas vary widely in aggressiveness, ranging from tumors that are slow growing and noncancerous (benign) to cancerous (malignant) tumors that are highly aggressive. The World Health Organization classifies gliomas on a grading scale from 1-4.

Grade 1 tumors are benign and don’t usually invade nearby healthy tissue.
Grade 2 tumors are slow-growing, but may spread to nearby tissue and sometimes progress to a higher grade over time.
Grade 3 tumors are malignant and can spread throughout the nervous system.
Grade 4 tumors are the most aggressive, growing rapidly and often returning after treatment.

The treatment approach for a glioma will depend on the grade of the tumor, but may involve surgery, radiation, chemotherapy, or other treatments. Low-grade tumors are more easily treated and surgery alone can sometimes be curative. On the other hand, high-grade tumors typically require more aggressive treatment that involves surgery and other types of treatment.

There are also several other factors that might influence a glioma treatment plan, including:

a person’s age and general health
the molecular and genetic characteristics of the tumor
the location of the tumor within the brain or spinal cord
patient preferences and personal factors.

A multidisciplinary team of healthcare professionals, including neurosurgeons, oncologists, neurologists, and others will likely be involved in deciding the best treatment plan. Patients should take an active role in this process and talk thoroughly with their healthcare team about surgery, radiation, and chemotherapy risks and benefits. Glioma treatment may also affect fertility, so patients should talk with their doctors about fertility preservation options.

Surgery

Surgery to remove as much of the tumor as possible is generally the first approach to brain cancer treatment.

Even if a tumor is benign, surgery is often considered when the tumor presses on healthy brain tissue and causes problems. Low-grade tumors may be able to be completely removed with surgery and may not require additional treatment.

High-grade gliomas — especially a very aggressive form of astrocytoma called glioblastoma — are harder to completely remove with surgery, but doctors will still try to remove as much of the tumor as they can to ease symptoms and slow disease progression. These patients usually require additional treatments after surgery, called adjuvant therapy, to attempt to kill the remaining cancerous cells.

Surgery to remove a glioma

The most common type of surgery for a brain tumor is called a craniotomy, where a surgeon cuts open the skull near the tumor to remove the affected tissue. They might use imaging, such as an MRI scan, to guide them to exactly the right location. After the tumor is removed, the surgeon will secure the skull and skin back in place with metal brackets and stitches.

A craniotomy is usually performed under general anesthesia, meaning the patient is not awake. Sometimes, however, an awake craniotomy may be performed if the tumor is close to parts of the brain that serve very important functions. This allows the surgeon to ask patients to perform tasks during the surgery as a way of monitoring their neurological function. A person will not feel any pain during the procedure — the brain itself does not have pain receptors so it can’t feel pain — and all other tissues will be numbed with anesthesia.

Keyhole brain surgery, or a neuroendoscopy, is a less invasive procedure that might be used instead of a craniotomy in some cases. It’s performed with a long tube called an endoscope that’s inserted into a small hole cut in the skull. The endoscope is equipped with a camera and small surgical tools which enable surgeons to view and remove tumors through a minimally invasive approach.

Ideally, the goal of glioma surgery is to remove the entire tumor (a total resection), but this is not always feasible. In such instances, a surgeon will remove as much of the cancer as is safely possible (subtotal or partial resection) in order to ease symptoms and slow the cancer’s progression. A subtotal resection might be required when:

a tumor has diffusely invaded surrounding tissue and can’t be separated easily from healthy tissue
the tumor is in a very delicate area that could be easily damaged.

Sometimes, if the tumor can’t be removed safely, surgery might not be an option at all. Examples of glioma types where surgery may not be performed include:

diffuse intrinsic pontine glioma (DIPG), an aggressive glioma where the tumor is located in the brainstem, a part of the brain critical for involuntary functions like breathing and heart rate. DIPG treatment usually starts with radiation.
certain optic gliomas, which are usually slow growing, but are near nerves critical for vision. Optic glioma treatment often starts with chemotherapy.

Other surgeries

Beyond removing the tumor, there are a few other reasons surgery might be required in people with a glioma. These include:

to get a tissue sample for a biopsy
to drain fluid buildup and relieve pressure inside the skull that’s causing symptoms such as headaches or nausea
to administer chemotherapy directly to the tumor or insert a device through which chemotherapy can be delivered later.

These procedures may be done at the same time as surgery to remove the tumor, or as a separate procedure, depending on the individual situation.

Side effects and risks

As with all major surgeries, glioma surgery comes with some risks. Some possible complications include:

swelling in the brain
seizures
weakness and dizziness
a loss of normal brain functions.

A person’s doctors will carefully monitor them for these complications in the days and weeks after surgery. To minimize the risk of brain swelling following surgery, patients are usually prescribed corticosteroids before surgery and for a few days post-surgery.

It’s important to let a healthcare provider know about any unexpected changes during recovery.

Radiation therapy

Radiation therapy involves the use of beams of powerful energy, usually from X-rays, to kill tumor cells. In glioma patients, it’s often used after surgery to kill off remaining cancer cells, although it may also be the first treatment option if surgery is not possible.

Radiation therapy is not usually used in children younger than age 3, however, because of the possible long-term impacts on brain development.

Most often, radiotherapy for glioma involves external beam radiation therapy, where a machine delivers radiation from outside the body. It’s usually delivered in short daily sessions over several weeks.

Radiation can also damage healthy brain tissue, so the goal is to deliver the radiation as precisely as possible to the location of the tumor. Doctors may use a number of different types of radiotherapy to achieve that, depending on the goal of treatment. One example is stereotactic radiotherapy, where a large, but very precise dose of radiation is administered to the tumor from several angles. This might be used for tumors in the brain or spinal cord that can’t be easily treated with surgery, or for people who are not healthy enough for surgery.

Sometimes, internal radiation therapy or brachytherapy, which involves inserting radioactive material directly into or near the tumor, might be used. In this approach, the radiation source can be implanted during surgery to remove the tumor, or later, if a tumor returns.

Side effects of radiation treatment will depend on the type and dose of radiation a person receives. Some common short-term side effects of brain cancer radiation, which usually go away after treatment, include:

fatigue or weakness
hair loss or thinning
nausea and vomiting.

Radiotherapy has advanced significantly in recent years, so long-term complications aren’t as common. Still, some long-term effects of glioma radiotherapy may include:

problems with thinking and memory
areas of dead cells, or necrosis, in the brain
hormonal changes
a second brain tumor
vision changes.

Chemotherapy

Chemotherapy is a large class of medications that work in different ways to stop cancer cells from growing. Glioma patients usually receive chemotherapy in combination with radiation to kill off remaining cancer after surgery, but it can also be used when surgery is not possible or if cancer returns after other treatments. Chemotherapy might be used instead of radiation in young children.

A number of chemotherapy agents can be used, alone or in combination, in people with gliomas. These include:

carboplatin
cisplatin
Gleostine (lomustine)
Matulane (procarbazine)
temozolomide (sold as Temodar and generics)
vincristine.

Chemotherapy is most often taken by mouth or infused into the bloodstream, and given in cycles with specific days of treatment and rest periods in between. However, some chemotherapies cannot reach the brain due to their inability to cross the blood-brain-barrier, a semipermeable membrane that protects the brain and spinal cord from the external environment. In these situations, chemotherapy can be administered directly into the cerebrospinal fluid, the liquid which surrounds the brain and spinal cord.

In some cases of glioblastoma, after surgery to remove a tumor, a surgeon will place dissolvable wafers containing a chemotherapy drug called carmustine (sold as Gliadel wafers) directly onto parts of the brain tumor that couldn’t be removed. The wafers will slowly dissolve over a couple of weeks as they release the chemotherapy.

Chemotherapy can effectively kill cancer cells, but it also damages healthy cells, leading to a wide range of side effects. The specific ones will vary based on the medications that are used, but some common chemotherapy side effects include:

hair loss
mouth sores
fatigue
nausea, vomiting, and appetite loss
gastrointestinal issues, including diarrhea or constipation
increased infection risk
easy bruising or bleeding.

Targeted therapies

Targeted therapies are a class of medications specifically designed to hone in on genetic changes in cancer cells that make them different from normal cells. Unlike standard chemotherapy, this helps them specifically kill cancer cells while minimizing the damage to healthy cells.

These treatments are not widely used in glioma care, but there are a few that may be prescribed, especially when other treatments haven’t worked. To be eligible for some targeted therapies, a person’s tumor may have to be tested to see if the cells have the specific characteristics that the medication targets.

Targeted therapies can be administered as an into-the-vein (intravenous) infusion or orally as pills or tablets.

Bevacizumab (sold as Avastin, among others) is an antibody-based medication approved for treating certain glioblastomas that have come back after treatment. It targets a protein called VEGF that tumors use to form new blood vessels to support their growth.
Voranigo (vorasidenib) is approved in the U.S. for use after surgery in certain patients with astrocytomas or oligodendrogliomas with mutations in the IDH1 or IDH2 genes.
Everolimus (sold as Afinitor, among others) is a once daily pill that blocks a protein called mTOR that normally helps cancer cells grow. It can be used in people with certain astrocytomas that can’t be completely removed with surgery.

Common side effects of targeted therapies include:

feeling tired or weak
nausea
headaches
loss of appetite
diarrhea.

Tumor treating fields therapy

Tumor treating fields, or TTFields, is sometimes an option for people with aggressive glioblastomas. It noninvasively delivers electrical energy onto the glioma, which disrupts the process of cell division in rapidly dividing cells, such as tumor cells. As normal adult brain cells divide slowly, they are not affected by the electrical fields.

A wearable TTFields device called Optune Gio is approved in the U.S. for glioblastoma patients. It can be used alongside chemotherapy for newly diagnosed patients after they’ve had surgery, or on its own for patients whose cancer has come back after other treatments.

Optune Gio involves placing adhesive patches on the head that contain electrodes connected to a portable battery-powered device, which creates alternating electrical fields that target tumor cells. It’s intended to be worn and turned on continuously for at least 18 hours a day. The device itself can cause minor side effects such as skin irritation or sores.

Emerging treatments

There are several other treatment strategies that are being tested in clinical trials as possible glioma therapies, especially for difficult to treat glioblastomas.

Of particular interest are immunotherapies, which work in various ways to boost the immune system’s ability to kill cancer cells. These include:

immune checkpoint inhibitors, such as Keytruda (pembrolizumab) and Opdivo (nivolumab)
therapeutic vaccines
cell-based therapies
CAR T-cell therapies.

Another area of interest for treating glioma is gene therapy, wherein genetic material is introduced into tumor cells to either inhibit their ability to replicate or make them more sensitive to other treatments. There are also a variety of other brain cancer treatment drugs that are under investigation.

Participating in clinical studies is a way to gain access to new treatment options that aren’t yet available on the market. Still, because these treatments are experimental, there’s no guarantee they’ll work to slow the cancer’s growth and their side effects are not fully known. Patients who wish to participate in a clinical study should talk with their doctors about whether there are any trials for which they may be eligible, and discuss the potential benefits and risks of participating in one.

How treatment affects life expectancy

Glioma treatments can have a substantial impact on a person’s life expectancy. Particularly, the extent to which a glioma can be removed during surgery is a major factor that influences survival.

Most slow-growing grade 1 gliomas are surgically curable and will not affect life expectancy. However, the prognosis is much worse for aggressive gliomas that are not completely removable with surgery and are likely to return later.

Other treatments used after surgery can help slow the cancer’s growth and extend survival, but even when used aggressively, they are unlikely to cure patients. High-grade glioma life expectancy with treatment is still low, with only around 5% to 30% of patients living five years or more past their diagnosis.

While treatment can have a strong influence on patient outcomes, a number of other factors, such as age and general health status, can influence brain cancer life expectancy. A doctor may be able to factor in several of these to provide an estimate about how surgery or any other treatment will affect a person’s prognosis.

Palliative care and rehabilitation

In addition to primary glioma cancer treatment, patients are likely to receive a variety of supportive treatments to help manage symptoms, prevent complications, and ease treatment-related side effects. This is also known as palliative care, and its main goal is to improve life quality at any stage of disease.

Palliative care for glioma may include:

pain management
medications to ease nausea and vomiting
mental health support
nutrition support
medications to control seizures
steroids to ease brain swelling
complementary treatments to improve life quality, such as acupuncture, meditation, or massage.

Brain cancer and its treatment can sometimes cause damage to healthy brain tissue, leading to neurological changes, including movement, speech, and cognitive issues, that make it harder for someone to go about their daily life. Even after treatment ends, patients may need rehabilitation to help regain lost abilities or to make adaptations that improve their daily living. These might include:

physical therapy, to help regain motor skills and muscle strength
occupational therapy, to help make it easier to go about daily activities like household chores and work
speech therapy, to recover from speech and communication difficulties
tutoring or other educational support, to help children manage changes in memory and thinking.

End-of-life care

For those with a terminal cancer diagnosis, glioma treatment is mainly focused on keeping patients comfortable and helping them cope in their remaining months or years. Palliative care, including measures to ease pain and other symptoms, is critical during this time.

Patients should work with their caregivers and healthcare providers to create an end-of-life care plan that will enable them to live as well as possible during that period.

Making these choices can be extremely difficult. There are social workers and other professionals at most cancer treatment centers that can help guide families and provide resources on making end-of-life decisions.

There may come a time when patients choose to stop active cancer treatments. At this point, hospice care, a holistic approach focused on allowing patients the best attainable physical and emotional quality of life at the end of life, might be of benefit.

Hospice care can be done at home or in a designated facility and usually involves a multidisciplinary team including doctors, nurses, social workers, spiritual advisors, and others who work together to support the patient.

Rare Cancer News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.