Meningioma
What You Should Know About Meningioma
A meningioma grows out from the coverings of the brain and spine, or meninges, pushing the brain away rather than growing from within it.
- Most are considered "benign" because they are slow-growing with low potential to spread.
- These tumors can become quite large. Diameters of 2 inches (5 cm.) are common
- Unusual meningiomas that grow quickly and exhibit cancer-like behavior are called atypical meningiomas or anaplastic meningiomas.
- Meningiomas represent about 20 percent of all tumors originating in the head and 10 percent of tumors of the spine.
- About 6,500 people are diagnosed with meningiomas each year in the United States.
- This type of tumor occurs more frequently in people with a hereditary disorder called neurofibromatosis type two, or NF-2.
Symptoms
- The most common symptoms are pain (headache) for weeks to months, weakness or paralysis, visual field reduction and speech problems.
- Specific symptoms depend upon the location of the tumor. See the chart below:
Most Common Sites and Symptoms for Meningiomas in the Head
| Location |
% of Total |
Common Symptoms |
| Frontal-parietal |
20 |
Seizures, local neurological deficits, intracranial hypertension, headache, extremity weakness, personality changes, dementia, urinary incontinence, difficulty speaking, visual field deficit. |
| Midline |
25 |
Seizures, local neurological deficits, intracranial hypertension, lower extremity weakness, sensory seizures, headache, personality changes, dementia, increasing apathy, flattening of affect, unsteadiness, tremor. |
| Sphenoid Ridge |
18 |
Eye-bulging, decreased visual acuity, cranial nerve (III, IV, V, VI) palsies, seizures, memory difficulty, personality change, headache. |
| Posterior Fossa |
10 |
Unsteadiness and incoordination, hydrocephalus (increased pressure inside the brain), voice and swallowing difficulties. |
| Pituitary Gland |
8 |
Lateral field visual deficit. |
| Olfactory Groove |
7 |
Loss of smell (anosmia), subtle personality changes, mild difficulty with memory, euphoria, diminished concentration, urinary incontinence, visual impairment. |
| Optic Sheath |
5 |
Decreased vision in one eye. |
| Other |
7 |
Variable depending on location. |
Diagnosis
- Magnetic resonance imaging (MRI) scans effectively detect most meningiomas and are best at displaying details of the brain..
- Sometimes a computed tomography (CT) scan is obtained as an initial screening scan in the evaluation of a headache. A CT scan is best at showing whether the tumor has invaded the bones of the skull or is calcified.
- Meningiomas are classified by pathologists into three types:
- Grade 1 - Benign: These very slow-growing tumors account for 75 percent of all meningiomas.
- Grade 2 - Atypical: Usually slow-growing but can recur.
- Grade 3 - Anaplastic: More malignant, faster-growing.
- The 15 percent of meningiomas that recur often progress to a higher grade. Grade 2 and 3 tumors recur more frequently than grade 1 types
Treatment
- Observation: May be appropriate in the following situations:
- Patients with mild or minimal symptoms, no impact on quality of life, and little or no swelling in adjacent brain areas.
- Older patients with very slowly progressing symptoms. Related seizures can be controlled with medication.
- Patients at significant risk of reduced quality of life due to treatment.
- Patients who choose to forego surgery.
- Surgery: Meningioma surgery varies from relatively straightforward to highly complex, requiring multiple surgeons from different specialties.
- The ease of removal depends upon both their accessibility and the skill of the neurosurgeon. UCLA brain tumor neurosurgeons have extensive experience in removing all types of meningiomas.
- The goal is to first preserve or improve neurological function and second to remove the tumor and all its attachments.
- When total removal of the tumor carries significant risk of morbidity (any side effect that can decrease quality of life), it's better to leave some tumor tissue in place.
- If the meningioma is near the surface and has not invaded deep structures or major blood vessels, resection (tumor removal by surgery) can be carried out safely.
- If the tumor invades any of the large draining veins, major arteries on the brain surface, or if it is on the underside of the brain, chances of a complete resection decrease and risk of complications increases.
- In many cases, minimally invasive, endoscopic-assisted techniques can be used.
- Angiography and embolization
- Some neurosurgeons prefer to shrink the meningioma using embolization before surgery. Embolization rarely is used as the only form of therapy.
- Angiography is the name of the x-ray test that uses a dye injection to locate and create an image of the major blood vessels in the brain and those feeding the tumor.
- Embolization involves threading a thin tube (catheter) up the leg veins or arteries directly into the blood vessels that feed the tumor. Then a glue-like clotting substance is injected to choke off and shrink the tumor.
- Radiation
- For those ineligible for surgery or with incomplete surgical removal, either conventional radiation or fractionated stereotactic radiosurgery (radiotherapy) can slow or stop the growth of meningiomas.
- Meningiomas have sharp margins and rarely invade neighboring tissue, thus they are ideal tumors for focused, shaped radiation fields using the Novalis Shaped-Beam Surgery.
- This technique does not require actual surgery, but instead uses advanced imaging and computer technology to deliver a high dose of radiation to the tumor while limiting radiation exposure to the surrounding brain structures.
- Unlike the Gamma Knife, which is limited to delivering single-dose treatments, the Novalis delivers narrow, well-defined beams that can better conform to the lesion for both single and multiple dose treatments.
Surgery and Radiation
- Surgery
- Eighty-five percent of all people with meningiomas are cured with surgery. In other words, the tumors do not return.
- Location, the amount of the tumor left after surgery, and the skill of the neurosurgeon are the important elements in predicting a successful result.
- Radiation
- Stereotactic radiosurgery stops the growth of meningiomas in about 80 percent of cases.
