Pituitary adenomas are tumors in the pituitary gland, located in the center of the head behind the eyes. The pituitary gland is less than a half inch in diameter, about the size of a pea. It's often called the "master gland" because it controls many of the body's other glands and the production of hormones, chemicals that regulate essential body processes.
If a pituitary tumor exists, the pituitary gland may make an excessive amount of hormones. Tumors that make hormones are called functioning tumors and those that don't make hormones are called nonfunctioning tumors.
Tumors that secrete hormones tend to be smaller than the pituitary gland when they're diagnosed. In fact, most pituitary tumors are microadenomas that measure 3 to 9 millimeters in diameter. Less common tumors are macroadenomas that are 10 millimeters or larger in diameter.
Tumors that don't secrete hormones, called endocrine-inactive adenomas, tend to be larger and may compress other tissue such as the optic nerves, causing vision loss.
Some tumors may cause Cushing's disease, in which too many hormones called glucocorticoids are released into the bloodstream. This causes fat to build up in the face, back and chest while the arms and legs become very thin. Other symptoms include too much sugar in the blood, weak muscles and bones, a flushed face and high blood pressure.
Other pituitary tumors can cause a condition called acromegaly, where the hands, feet and face are larger than normal. In very young people, the entire body may grow much larger than normal.
Almost all pituitary tumors are benign, rather than malignant or cancerous, and are relatively slow growing. They rarely spread to other areas of the body.
UCSF Medical Center is a major center for the diagnosis and treatment of pituitary disorders. The California Center for Pituitary Disorders at UCSF provides the most advanced diagnostic services and treatments including neurosurgery, radiation therapy and medication. The center is staffed by doctors who are known internationally for their expertise in treating pituitary tumors.
Patients with pituitary tumors may experience one or more of the following symptoms:
During your visit to UCSF's California Center for Pituitary Disorders, our medical team will ask you about your medical history as well as your immediate family's medical history. If your primary care physician has sent your previous medical records, we will review this information.
Be sure to tell your doctors about any medications you are currently using, including over the counter medications, vitamins, nutritional supplements or herbal remedies.
We will examine you in an attempt to discover the cause of your medical problem. This evaluation may include the following:
Pituitary tumors often can be removed safely through a neurosurgical procedure called transsphenoidal surgery. The word "transsphenoidal" describes the path the surgeon follows to reach the pituitary gland. The word comes from "trans," meaning "to cross or pass through," and "sphenoid," the name of the cavity, the sphenoid sinus, that is passed through to reach the pituitary gland. The operation now can be performed without any facial incision under the lip or in the nose.
The surgeon begins the approach to the pituitary gland by entering the nose on one side. The surgeon uses a very tiny microsurgical instruments especially designed for this particular operation and a brilliant fiberoptic light to illuminate the internal anatomy. In addition, a microscope magnifies the surgical area 12 times its actual size.
The surgeon then guides the instrument into the nasal cavity and an opening is made in the sphenoid bone. Once through the sphenoid sinus, an opening is made in the wall of the sella turcica to expose the pituitary gland.
Reviewed by health care specialists at UCSF Medical Center.