For patients with pituitary tumors, headaches may occur. Most patients in the early stages often experience mild headaches located behind the eye sockets, the forehead, and on both sides of the temporal area. These headaches are generally tolerable and occur intermittently. They are mostly caused by the stimulation of the tumor or the increased pressure inside the sella. When the tumor enlarges to a certain extent and breaks upward through the diaphragm sellae, headaches are often alleviated. However, if the tumor further grows into surrounding tissues, it might compress important blood vessels and nerves, resulting in recurring pain with increasing severity.