Because these tumors do not invade surrounding tissue or spread metastatically they are classified as benign. They are twice as common in females than in males. The pituitary gland is attached by a thin stalk to the base of the brain. The gland is comprised of two component parts, an anterior and a posterior portion. It is an endocrine gland which releases hormones into the blood that control a variety of body functions including growth, metabolism, water balance, and menstruation.
Pituitary adenomas are also benign and compress rather than invade surrounding tissue.
Gliomas tend to become increasingly malignant over time. These tumors are associated with a much more favorable prognosis. Typically, patients who have undergone surgical removal of the tumor survive for a prolonged time period. Pituitary adenomas also have a favorable prognosis following surgical resection. The prognosis of a pineal tumor is dependent on whether the tumor is benign or malignant.