Possible causative factors for this edema, e.g., tumor volume, tumor location, vascular supply, venous obstruction, histology, vascular endothelial growth factor (VEGF) production, and interleukin-6 expression, have been studied, but the exact mechanism of development of cerebral edema in meningioma patients remains unclear [4, 17, 21, 36]. The gene discussed is IL6; the disease is meningioma.