A normal pituitary gland releases many hormones that your body needs to function. The other organs in your body send signals back to the pituitary gland that help it keep sending the right amount of hormones when they're needed.
If you have a pituitary disorder, the pituitary gland may make too much or too little of a certain hormone. Some pituitary disorders affect more than one hormone. When these hormones are out of balance, your body does not function normally, and you can feel very sick.
Benign (non-cancerous) tumors called adenomas are the most common cause of pituitary disorders.
Other pituitary disorders
Most pituitary tumors (more than 80 percent) are adenomas (non-cancerous tumors). Some pituitary tumors are malignant (cancerous) and need surgery, radiation or chemotherapy to prevent serious illness or death. Many of these tumors affect the pituitary gland and the hypothalamus.