Surgical and Radiation Treatment of Skull Base Meningiomas

Meningiomas comprise approximately 20% of adult primary intracranial neoplasms. Of these, benign meningiomas are known to have an indolent growth pattern, usually without infiltration into adjacent nervous tissue. Because meningiomas have a well-circumscribed character, surgery has historically been the preferred treatment when total resection can be achieved with reasonable morbidity. Surgical resection has resulted in five-, 10-, and 15-year progression-free rates of 93, 80, and 68%, respectively. Despite the development of multiple techniques designed to minimize morbidity while obtaining a surgical cure, however, complete resection remains difficult and is not achievable in approximately 20–30% of presenting patients because of multiple regional involvement, severe adherence to or invasion of the brainstem, involvement of cranial nerves, or encasement of the vertebrobasilar circulation. Currently, controversy exists as to whether skull base meningiomas, especially those involving the petroclivus and/or cavernous sinus, are best treated with radical resection, subtotal resection followed by radiosurgical treatment of the residual lesion, or radiosurgical treatment alone.