Meningiomas 

Meningiomas tend to grow inward, putting pressure on the brain or spinal cord. However, they may grow outward and cause the skull to thicken. They may also contain cysts, calcifications or tightly packed blood vessels. This type of tumor may become large before it interferes with normal brain functions, and some meningiomas have receptors that interact with hormones. Although the exact relationship is not clear, researchers have observed that meningiomas sometimes grow faster during pregnancy.

Treating Meningiomas
Low-grade meningiomas are often treated with surgery alone. High-grade tumors are treated with a combination of surgery, radiation and/or chemotherapy. Low-grade meningiomas can become high grade, or can recur, in case which surgery, radiation and chemotherapy may be used.