Meningiomas are tumours that originate in the meninges, the outer layers of tissue that cover and protect the brain and spinal cord. They can be benign (noncancerous), malignant (cancerous and spreading to other parts of the body) or atypical (in between benign and malignant, but can turn cancerous).
The exact cause of a meningioma is unknown. Some of the risk factors can include previous radiation therapy to the head, female hormones and an inherited disorder known as neurofibromatosis type 2.
Meningiomas may lead to symptoms such as blurred or double vision, loss of smell, memory and hearing, headaches that get worse with time, seizures and weakness in your legs or arms. When you present to the clinic with these symptoms, your doctor reviews your medical history and diagnoses meningioma with imaging tests such as CT and MRI scans.
Treatment depends on the size, location and type of the tumour, and your overall health. Slow-growing, small and asymptomatic meningiomas do not require immediate treatment, but need to be monitored constantly for signs of growth. Tumours that require treatment may be indicated for the following:
- Surgery is performed to remove the tumour completely. For situations in which complete removal can damage surrounding tissues, your doctor excises as much of the tumour as possible and then destroys the remaining tumour with other treatments.
- Stereotactic radiosurgery is a type of radiation treatment that precisely targets high-energy radiation on small benign leftover tumours.
- Radiation therapy is indicated for atypical or malignant cancers, and after surgery to destroy remnant cancer cells. It uses high-energy beams of radiations to destroy the cancer cells and ensure non-recurrence.
- Fractionated radiation involves directing small doses of radiation onto the cancer, across many days. This is indicated for tumours too large for radiosurgery or those located in sensitive regions, such as the optic nerve region, which cannot withstand high-intensity radiations.