Benign brain tumor

Overview

A benign brain tumor is a growth of cells in or near the brain that is not cancerous. Benign brain tumors may start in the brain. Or they may start in nearby structures, such as the membranes that cover the brain, the pituitary gland, or the nerves involved in hearing and balance.

Benign brain tumors generally do not spread to distant parts of the body the way cancerous tumors can. Many benign tumors grow slowly. But a benign brain tumor still can be serious. It can cause symptoms if it presses on brain tissue, nerves, blood vessels or pathways for cerebrospinal fluid. Cerebrospinal fluid is the fluid that surrounds the brain and spinal cord.

Benign brain tumors often can be monitored or treated with surgery, radiation therapy or radiosurgery. Medicines may be used for some types, such as certain pituitary tumors. Symptoms and treatment for a benign brain tumor depend on the tumor's type, size, location, growth rate and molecular features and a person's overall health.

There are many types of benign brain tumors. The type is based on where the tumor starts and what kinds of cells make up the tumor. Common types include:

• Meningioma. A meningioma starts in the membranes that cover the brain and spinal cord, called the meninges. Meningioma is the most common type of benign brain tumor in adults.
• Pituitary adenoma. This type starts in the pituitary gland, a small gland at the base of the brain. Pituitary adenomas may affect hormone levels. They also may affect vision if they press on the optic nerves or optic chiasm. The optic chiasm is the place at the base of the brain where the two optic nerves cross.
• Vestibular schwannoma, historically referred to as acoustic neuroma. This tumor starts on a nerve involved in hearing and balance. Vestibular schwannomas may cause hearing loss, ringing in the ear, balance problems or dizziness.
• Craniopharyngioma. This type starts near the pituitary gland and the optic nerves. It may affect hormone levels, growth, vision and other functions.
• Hemangioblastoma. This rare, benign tumor often forms in the brain or spinal cord. Hemangioblastoma may happen on its own or as part of a genetic condition called von Hippel-Lindau disease.
• Glioma. Glioma is a growth of cells that starts in the brain or spinal cord. Some gliomas grow slowly and are considered low grade. These may include pilocytic astrocytoma or ganglioglioma. Even when a glioma grows slowly, it may need long-term follow-up because it can grow, come back after treatment or change over time.

Causes

The cause of most benign brain tumors isn't known. Most primary brain and other central nervous system tumors happen sporadically. This means they happen without a known inherited cause. Some tumor types have been linked to changes in genes or chromosomes. These changes can affect how cells grow and behave.

Some benign brain tumors are linked to genetic conditions that can run in families.

Examples include:

• Neurofibromatosis type 1, which is linked to optic pathway gliomas, meningiomas and tumors of nerves, called neurofibromas.
• NF2-related schwannomatosis, also called neurofibromatosis type 2, which is linked to vestibular schwannomas, meningiomas and ependymomas.
• Von Hippel-Lindau disease, which is linked to hemangioblastomas.
• Tuberous sclerosis, which is linked to a rare, slow-growing brain tumor called subependymal giant cell astrocytoma.
• Multiple endocrine neoplasia, type 1, which is linked to pituitary adenomas.

Complications

A benign brain tumor is not cancer. But it still can cause serious health issues. Complications depend on the tumor type, size, location and growth rate. Prompt evaluation and ongoing follow-up can help reduce the risk of serious complications.

Possible complications include:

• Seizures. A brain tumor can irritate nearby brain tissue and lead to seizures.
• Pressure in the brain. A tumor may block the flow of cerebrospinal fluid and cause fluid to build up in the brain. Cerebrospinal fluid is the fluid that surrounds the brain and spinal cord. Buildup of this fluid can cause nausea, headaches and, sometimes, vomiting.
• Vision problems. Tumors near the optic nerves, the optic chiasm where the optic nerves cross, or pituitary gland may cause vision changes or vision loss.
• Hearing and balance problems. Vestibular schwannomas, also called acoustic neuromas, can affect hearing and balance. Larger tumors may increase the risk of hearing loss.
• Hormone problems. Pituitary tumors can cause the pituitary gland to make too much or too little of certain hormones. This may affect growth, sex hormones, thyroid function, stress hormone levels, menstrual periods, fertility, energy level or body changes.
• Changes in movement, speech, thinking or memory. Tumors can affect nearby brain areas that control movement, language, thinking, memory or personality.
• Tumor growth or recurrence. Some benign brain tumors grow over time or come back after treatment. Long-term follow-up imaging may be needed. 

Treatment

Treatment for a benign brain tumor depends on the tumor type, size, location and growth rate. It also depends on symptoms, test results, molecular features, a person's age and overall health, and whether the tumor is affecting important brain functions.

Some benign brain tumors can be checked with regular imaging. Others may need surgery, radiation therapy, radiosurgery, medicines, rehabilitation or supportive care.

Monitoring

Some benign brain tumors do not need treatment right away. The approach to these tumors may be called observation, watchful waiting or active monitoring. Monitoring means your healthcare team checks the tumor over time with imaging tests, such as MRI, and watches for new symptoms or tumor growth.

Monitoring may be an option when a tumor is small, is not causing symptoms or is not pressing on important brain structures. This approach also may be used when the risks of treatment are greater than the likely benefit. If the tumor grows or symptoms develop, treatment may be recommended.

Surgery

Surgery may be recommended if a benign brain tumor is causing symptoms, growing, pressing on important structures or needs to be removed to confirm the diagnosis. The goal is to remove as much of the tumor as safely possible while protecting brain and nerve function.

Surgery also can provide tissue for lab testing. Testing the tissue can confirm the tumor type and show molecular changes that may help guide treatment and follow-up. Molecular changes are changes in the tumor's genes or other cell features.

Surgical approaches and techniques may include:

• Craniotomy. A craniotomy is surgery that removes a section of skull bone so the surgeon can reach the brain tumor. The tumor is removed with special tools. Sometimes lasers are used to destroy tumor tissue. In some cases, awake brain surgery is used to help lower the risk of affecting important parts of the brain. When the tumor removal is done, the skull bone is put back in place.
• Endoscopic transnasal transsphenoidal surgery. This surgery uses a long, thin tube with a camera, called an endoscope. The endoscope and special surgical tools are passed through the nose and sinuses to reach the pituitary area. This approach may be used for some pituitary tumors.

Sometimes the whole tumor cannot be removed safely. This can happen when the tumor is close to areas that control movement, speech, vision, hearing or other important functions. In these cases, the surgeon may remove part of the tumor to lower pressure, improve symptoms or get tissue for diagnosis. If the tumor is in a hard-to-reach area, a biopsy may be done to get tissue for testing and to help plan treatment.

Some benign brain tumors need no further treatment after they are removed. Others need ongoing imaging or more treatment if part of the tumor remains, the tumor grows or the tumor comes back.

Radiation therapy

Radiation therapy uses high-energy beams to damage tumor cells. It may be used when surgery is not possible, when part of the tumor remains after surgery or when a tumor comes back. Radiation therapy also may be considered when surgery could cause too much risk to important brain or nerve functions. Radiation therapy may be given in multiple treatments over time.

Radiosurgery

Stereotactic radiosurgery for brain tumors is an intense form of radiation treatment. It doesn't involve making a cut in the skin. It aims beams of radiation from many angles at the brain tumor. Each beam isn't very powerful. But the point where the beams meet gets a very large dose of radiation that kills the tumor cells.

Radiosurgery may be used for some benign brain tumors, including some meningiomas and vestibular schwannomas. It may be an option for small tumors, tumors that are hard to reach with surgery, tumors that remain after surgery or tumors that come back.

Types of radiosurgery technology may include:

• Gamma Knife radiosurgery. This treatment uses many small beams of gamma radiation aimed at the tumor.
• Linear accelerator radiosurgery. This treatment uses carefully shaped X-ray beams aimed at the tumor from different angles.
• Proton beam therapy. This treatment uses proton beams. It may be considered in some situations to limit radiation to nearby tissue. Proton beam therapy is the newest type of radiosurgery. It's becoming more common but isn't available at all hospitals.

Medicines

Medicines may be used to treat symptoms caused by the tumor or hormone issues related to the tumor.

Medicines may include:

• Antiseizure medicines. These medicines may be used for people who have seizures. The medicines are not typically used to prevent seizures in people who have never had one.
• Hormone-related medicines. Some pituitary tumors called prolactin-secreting pituitary tumors or prolactinomas can be treated with medicines called dopamine agonists. These medicines lower prolactin levels and may shrink prolactinomas. Other pituitary tumors may need monitoring, surgery or other treatments.

Chemotherapy and targeted therapy

Chemotherapy and targeted therapy may be considered for some low-grade gliomas. These treatments also may be used for some tumors with specific molecular changes, such as papillary craniopharyngioma. Treatment decisions depend on the tumor type, grade and molecular features, along with age and how much tumor remains after surgery.

Targeted therapy uses medicines that act on specific changes in tumor cells, called mutations. Treatment decisions for tumors with molecular changes depend on the full diagnosis and the person's situation.

Rehabilitation and supportive care

Some people need help recovering after treatment or managing symptoms caused by the tumor. Rehabilitation and supportive care may include:

• Physical therapy for strength, movement or balance.
• Occupational therapy for help with daily activities.
• Speech therapy for speech, language or swallowing concerns.
• Vision support.
• Hearing support.
• Help with memory, thinking or learning changes.
• School or workplace support for children or adults if the tumor or treatment affects learning, memory or development.

For some vestibular schwannomas, vestibular rehabilitation before surgery may help with movement and balance after surgery.

Recovery after surgery

Recovery after surgery depends on the tumor type, size and location. It also depends on the type of surgery, whether the whole tumor could be removed and whether the tumor affected important brain functions before surgery.

After surgery, the healthcare team watches for changes in brain and nervous system function. Imaging may be done to see how much of the tumor was removed and to help plan follow-up care. Some people go home after a short hospital stay. Others need more time in the hospital or need rehabilitation before going home.

Enhanced recovery programs help people prepare for surgery and recover afterward. For people having planned craniotomy for a brain tumor, these programs may help shorten the hospital stay and lower costs without increasing surgery-related complications.

Follow-up care is important after surgery. Some tumors need regular imaging to watch for tumor growth or recurrence. Follow-up schedules depend on the tumor type, how much tumor was removed and whether the tumor changes over time.

Coping and support

Some people say a brain tumor diagnosis feels overwhelming and frightening. It might make you feel like you have little control over your health. It may help to take steps to understand your condition and talk about your feelings. Consider trying to:

• Learn enough about brain tumors to make decisions about your care. Ask your healthcare professional about your specific type of brain tumor. Ask about your treatment options and, if you like, your prognosis. As you learn more about brain tumors, you may feel better about making treatment decisions.
• Keep friends and family close. Keeping your close relationships strong can help you deal with your brain tumor. Friends and family can provide the practical support you'll need, such as helping to take care of your home if you're in the hospital.
• Find someone to talk with. Find a good listener who is willing to hear you talk about your hopes and fears. This may be a friend, family member or clergy member. Ask your healthcare team to suggest a counselor or medical social worker you can talk with.

Ask your healthcare team about brain tumor support groups in your area. It can be helpful to learn how others in the same situation are coping with complicated medical conditions.

Survival rates

Survival rates by tumor location

Ten-year survival rates are reported by tumor location for all ages combined. These rates are not specific to adults or children. But these rates can still be useful because survival varies by where the tumor starts.

These are survival rates by tumor location, not by exact tumor diagnosis. The rates are based on primary benign brain and other central nervous system tumors reported in the United States from 2004 to 2021.

Some benign or low-grade brain tumor types are not listed in the table because they do not match one clear tumor-location category. Low-grade gliomas, for example, can start in different areas of the brain. Hemangioblastomas often form in the central nervous system, but the survival data do not provide a clear benign hemangioblastoma location category. For these tumors, prognosis depends on the exact tumor type, location, size and growth rate, whether the tumor can be removed or controlled, and whether it affects important brain functions.