Benign Brain Tumors
Noncancerous growths in or around the brain
Quick Facts
- Type: Neurological condition
- Nature: Noncancerous, usually slow-growing
- Common types: Meningioma, pituitary adenoma, acoustic neuroma
- Key concern: Pressure on nearby brain tissue
Overview
Benign brain tumors are noncancerous growths that develop in or around the brain. Unlike cancerous (malignant) tumors, they generally grow slowly, have clear borders, and do not spread to other parts of the body. Even so, because the skull is a fixed space, a benign tumor can still cause problems by pressing on nearby brain tissue, nerves, or blood vessels.
Common types include meningioma (arising from the brain's coverings), pituitary adenoma (in the pituitary gland), and acoustic neuroma (on the nerve to the ear). Many benign brain tumors are highly treatable, and some are simply monitored if they cause no symptoms.
The word benign can be reassuring, but its meaning is more limited inside the skull than elsewhere in the body. Because there is no room for a growth to expand without pressing on something, even a slow, noncancerous tumor in a critical location can cause significant symptoms. For this reason, decisions about treatment depend not only on whether a tumor is cancerous but also on its size, location, and whether it is growing.
Symptoms
Symptoms depend on the tumor's size and location and result from pressure on nearby structures:
- Headaches, sometimes worse in the morning
- Seizures
- Vision or hearing changes
- Balance problems or dizziness
- Weakness or numbness in part of the body
- Changes in memory, personality, or concentration
- Hormone-related symptoms with pituitary tumors
Sudden severe headache, new seizures, sudden weakness, vision loss, or confusion should be evaluated urgently. Because many benign tumors grow slowly, symptoms may develop so gradually that they are easy to overlook or attribute to stress or aging. A change in headaches, especially ones that are new, worsening, or worse in the morning, is worth discussing with a doctor.
Causes
In most cases the exact cause of a benign brain tumor is unknown. Tumors form when cells in or around the brain grow and divide more than normal. Contributing factors can include:
- Genetic conditions: Certain inherited syndromes increase the risk of specific tumors.
- Prior radiation: Past radiation to the head can raise the risk.
- Age: Some tumors are more common with increasing age.
For the great majority of people, there is no identifiable cause and nothing they did to bring on the tumor.
Risk Factors
- Increasing age for some tumor types
- A history of radiation therapy to the head
- Certain inherited genetic syndromes
- A family history of brain tumors in some cases
Diagnosis
Diagnosis usually involves a neurological evaluation and imaging:
- Neurological exam: Testing vision, hearing, balance, strength, reflexes, and coordination.
- MRI: The main imaging test, providing detailed pictures of the brain and tumor.
- CT scan: Sometimes used, especially when MRI is not available.
- Biopsy: A sample of tissue may be needed to confirm the type, depending on the tumor and its location.
- Hormone tests: For pituitary tumors.
Treatment
Treatment depends on the tumor's type, size, location, and whether it causes symptoms:
- Watchful waiting: Small, symptom-free tumors may simply be monitored with periodic imaging.
- Surgery: Removal of the tumor is often the main treatment when it causes symptoms or is growing.
- Radiation therapy: Including focused techniques, used when surgery is not suitable or to treat remaining tumor.
- Medications: Such as those that shrink certain pituitary tumors or control symptoms like seizures or swelling.
Many people do very well after treatment, especially when a tumor can be fully removed. The right approach is highly individual and is usually decided by a team that may include a neurosurgeon, a radiation specialist, and other experts. Even after successful treatment, periodic follow-up imaging is common to make sure the tumor does not return or regrow.
Prevention
Most benign brain tumors cannot be prevented because their cause is unknown. Helpful steps include:
- Attending recommended follow-up imaging if you have a known tumor
- Reporting new or worsening symptoms promptly
- Seeking genetic counseling if you have an inherited syndrome linked to brain tumors
- Following medical advice after any prior head radiation
When to See a Doctor
See a doctor for persistent or worsening headaches, vision or hearing changes, balance problems, or memory and personality changes. Seek emergency care right away for:
- A sudden, severe headache unlike any before
- A first-time seizure
- Sudden weakness, numbness, or trouble speaking
- Sudden vision loss or severe confusion
Frequently Asked Questions
Are benign brain tumors dangerous?
Benign brain tumors are noncancerous and do not spread, but they can still cause problems because the skull is a fixed space. A growing tumor may press on the brain, nerves, or blood vessels, leading to symptoms that sometimes need treatment.
What are the most common types?
Common benign brain tumors include meningiomas, which arise from the brain's coverings, pituitary adenomas in the pituitary gland, and acoustic neuromas on the nerve to the ear. Each type behaves differently and may need different treatment.
Do all benign brain tumors need treatment?
No. Small tumors that cause no symptoms are often simply monitored with periodic MRI scans. Treatment, such as surgery or radiation, is usually considered when a tumor causes symptoms, is growing, or is in a location that could become dangerous.
How are benign brain tumors treated?
Options include watchful waiting with imaging, surgery to remove the tumor, radiation therapy, and medications for certain tumors or to control symptoms. The best approach depends on the tumor's type, size, and location, and many people do well after treatment.
What symptoms need emergency care?
Seek emergency care for a sudden severe headache unlike any before, a first-time seizure, sudden weakness, numbness, or trouble speaking, sudden vision loss, or severe confusion. These can signal a serious problem needing immediate evaluation.
References
- American Brain Tumor Association. Benign Brain Tumors.
- Mayo Clinic. Brain tumor — Symptoms and causes.
- National Cancer Institute (NCI). Adult Central Nervous System Tumors Treatment.
- MedlinePlus, U.S. National Library of Medicine. Brain tumors.