Nonfunctional tumors are the second most common type of tumor in the pituitary gland. Even though these tumors do not produce pituitary hormones, nonfunctional pituitary tumors can grow and affect hormone secretion by the normal gland, leading to a condition called hypopituitarism.
Nonfunctional pituitary tumors occur most often in men between the ages of 50 and 60 and are less commonly diagnosed in women.
Nonfunctional pituitary tumors are usually not found until they have grown large enough to cause symptoms. As the tumor presses on the nearby optic nerve, symptoms may include headache and visual disturbances.
There can be other symptoms as well. Men with a nonfunctional pituitary tumor may experience loss of libido due to decreased testosterone. Women may develop irregular menstrual periods.
If your doctor suspects a nonfunctional pituitary tumor, an MRI scan may be ordered to determine the exact location and size of the tumor. We also perform blood tests to evaluate the levels of all the pituitary hormones.
Surgery is the most common treatment for large nonfunctional tumors. At Memorial Sloan Kettering, we use a minimally invasive procedure called transnasal transsphenoidal resection to remove pituitary tumors. Surgeons are able to bypass brain tissue, operating instead through an incision inside the nasal passage. The risk for neurologic complications with this approach is very low, and the surgery leaves no visible scar.
If surgery alone is not curative, radiation therapy may be an option. Forms of radiation therapy recommended may include external radiosurgery of “stereotactic radiosurgery” in which special equipment is used to give a single large dose of radiation to a tumor.
Intensity-modulated radiation treatment, which uses radiation beams of varying intensity to precisely match tumor angles and shapes and thereby reduce the risk of damage to optic nerves and other delicate structures in this area, is sometimes used as well.
There are currently no medications that have been shown to be effective for treating nonfunctional pituitary tumors.