Representing approximately one third of all primary brain tumours in adults, meningiomas are often-benign tumours that grow out of the meninges, which are the layers of tissue covering the brain and spinal cord. Meningiomas usually grow slowly and inward, causing pressure on the brain or spinal cord. Some contain cysts, mineral deposits (calcifications), or tightly packed bunches of blood vessels.
It is not known what causes meningiomas, but they have been associated with a history of breast cancer or neurofibromatosis type 2. Some tumours are known to interact with hormones, including progesterone, androgens, and estrogen, though the latter is less common. Due to their interactions with hormones, they can grow faster during pregnancy.
The principal treatment for meningiomas is surgery, but radiation therapy is used in cases where the tumour cannot be surgically removed. In some cases, if the tumour is not posing an immediate danger, doctors will “watch and wait” and conduct regular MRI scans.
Symptoms of meningioma usually result from pressure on the brain, rather than invasion of the brain tissue. They include headaches; changes in vision, such as seeing double or blurriness; weakness in an arm or a leg; and seizures. Changes in personality, confusion, and memory loss can also occur.
Information taken from WebMD.