A meningioma is a tumor that starts in the space between the skull and brain or the spine and spinal cord. It is the most common type of primary brain tumor.
When brain cancer is primary, this means that the tumor originated in the brain.
The outlook for a person with a meningioma depends on many factors, including the size of the tumor. Treatment usually involves surgery to remove the tumor. When this is not an option, other approaches, such as radiation, can help.
This article explores the symptoms, treatments, and types of tumors and the outlooks for each.
A meningioma is a type of brain or spinal cord tumor located in the meninges. The meninges are three membrane layers that surround the brain and spinal cord. The layers are called dura mater, arachnoid mater, and pia mater.
Meningiomas are the most common type of primary brain tumor. They grow on the dura mater, which is the outermost layer of the meninges.
The cells that line the dura mater are called meningeal cells. When these cells mutate, their genetic code changes, and this can affect how the cells function. As a result, they can transform into tumor cells.
Exposure to radiation, particularly during childhood, is the only known environmental risk factor for meningiomas. People living with a genetic disorder called neurofibromatosis type 2 also have a higher chance of developing meningiomas.
Some types of meningioma grow slowly and do not spread, while others spread quickly and are more dangerous.
There are three types, or grades, of meningiomas. A doctor assesses the grade based on characteristics such as:
- the tumor’s location
- its type
- the extent of spreading
- genetic findings
- the person’s age
- the amount of tumor that remains after surgery
A doctor grades meningiomas 1–3. Grade 1 is the most common type, and it grows slowly.
People with grade 2 meningiomas have a higher chance of the tumor returning after surgery to remove the initial tumor. Grade 3 meningiomas are rare but the most serious type.
Grade 2 and 3 meningiomas often spread or come back even after surgery.
Grade 2 meningiomas may spread from the meninges to surrounding brain and bone tissue. Grade 3 meningiomas can spread throughout the brain and other organs.
The cells of grade 2 meningiomas have an atypical appearance on microscopic examination. Those of grade 3 meningiomas have a very atypical appearance compared with healthy meningeal cells. Doctors describe this as an anaplastic appearance.
According to the National Cancer Institute, meningiomas are more common in females, but higher grades occur more often in males. Meningiomas are most common in Black people and people aged 60 years and older.
It is possible to cure some types of meningiomas. If a doctor detects it early and it is not causing symptoms, treatment may not be necessary right away. In this case, the doctor will regularly monitor the tumor and provide treatment options if the meningioma gets bigger or spreads.
If a surgeon removes the tumor completely, there is a high chance that it will not return. However, higher-grade tumors may come back.
Meningiomas with higher grades are more challenging to treat, and survival rates are lower for people with these types of cancer. Radiation therapy after surgery may help improve survival rates and reduce the chances of regrowth and spreading.
The symptoms of a meningioma depend on its location. Generally speaking, a meningioma may cause:
- headaches that are more intense in the mornings
- changes in vision
- loss of hearing
- loss of smell
Some people with meningiomas have no symptoms, so doctors need scans of the brain and spine to make a diagnosis.
First, a doctor takes a medical history and evaluates any symptoms. Some people with meningiomas have no symptoms, while others may experience neurological problems and headaches, for example.
Next, the doctor may need brain MRIs and CT scans. One preferred method is a contrast MRI, which involves injecting a dye into the person’s vein. This causes any tumor to appear bright or enhanced on the scan.
A doctor who suspects a meningioma may also use MRI spectroscopy, a type of imaging that can show whether cancer cells have spread to other areas of the brain or other organs.
Digital subtraction angiography is another imaging technique that can help. It shows which blood vessels are feeding a meningioma.
Before making a diagnosis, a doctor may remove a piece of the abnormal tissue, which a neuropathologist then checks for cancerous cells. This helps them determine whether the tumor is a meningioma or another type of cancer, and it also helps them assess the tumor’s grade.
The most effective approach to cancer treatment depends on the characteristics of the tumor and factors specific to the person.
Someone with a small tumor that causes no symptoms may not need treatment. In this case, the doctor may assess the tumor once or twice a year to check that it has not changed and is still causing no symptoms.
If a meningioma is causing symptoms, the first-choice treatment is usually surgery to remove the tumor. This is also true for any rapidly growing meningioma.
After the surgery, the doctor may recommend additional treatments to prevent the tumor from returning, such as:
If a person joins a clinical trial, they may have access to specific, targeted therapy and immunotherapy for their meningioma.
However, researchers are still mapping out the role of chemotherapy, immunotherapy, and targeted therapy in treating this type of tumor.
While drug-based treatments for meningiomas are still in the experimental stage, some of these treatments show
Survival rates vary depending on the grade of meningioma. They are highest for people with grade 1 tumors.
For people with grade 2 or 3 meningiomas, experts use the relative 5-year survival rate. This describes the percentage of people who live for at least 5 years after receiving their meningioma diagnosis. The 5-year survival rate for grade 2 and 3 meningiomas is almost 64%.
It is worth keeping in mind that doctors base all survival rates on averages of past data, and they may not consider recent advances in detection and treatment.
Also, many other factors can affect a person’s prognosis, including:
- the type of tumor
- its location
- other characteristics of the tumor
- the person’s age
- their general health
- their response to treatment
It is important to speak with the doctor to get a more accurate idea about the outlook.
A meningioma is a type of tumor that develops in the meninges — three membrane layers surrounding the brain and spinal cord.
Grade 1 meningiomas may not require treatment. Instead, the doctor may monitor the tumor and the person’s overall health once or twice a year.
When treatment is necessary, it involves surgically removing the tumor when possible. Some people with tumors that have higher grades need additional treatment to prevent the tumor from returning or spreading.