The pituitary gland is a small gland located atthe base of the skull just below the optic nerve. It is in charge withproduction of many hormones which control and provide with proper functioningof other glands in human body.
Pituitary tumor is abnormal growth of thepituitary cells. Pituitary tumors can be benign or malign. In benign form ofthe disease the tumor only grows but it does not spread to other parts of thebrain. Malign tumors invade and destroy surrounding structures and may spreadto other parts of the brain. Fortunately, almost all pituitary tumors arebenign. Furthermore, these tumors may be hormonally active or they do notproduce hormones or other substances. Hormonally active pituitary tumorsproduce excessive amount of certain pituitary hormones.
Symptoms and Signs of Pituitary Tumors
Symptoms and signs of pituitary tumors are relatedto both direct growth and pressure of the tumor and occur due to a change innormal hormonal levels. The growth of the tumor causes compression of the opticnerve which eventually results in visual disturbances. In large tumors patientsusually complain about headaches.
Increase in hormones leads to specific symptomsand signs depending on which hormone is increased. For example, prolactin-secreting tumors cause production of small amounts of milk and may cause stopin menstrual cycles. This tumor is also responsible for infertility in bothgenders. Pituitary tumors which produce excessive amount of growth hormone causegigantism. If the tumor produces too much TSH there are symptoms and signs ofthyroid dysfunction. Overproduction of ACTH leads to Cushing's syndrome.
Tumors of posterior part of the pituitary glandare rather rare. Still if they occur they may induce diabetes insipidus. Basiccharacteristics of this disease are increased thirst and passing large amountsof urine.
Diagnosing Pituitary Tumors
If there is elevation in certain hormones thedoctor may assume patient is suffering from pituitary tumor and the patientthen undergoes CT scan or MRI of the head. These two imaging methodssuccessfully visualize the tumor. Neurologic testing gives information onwhether there is a damage to the brain and cranial nerves by the tumor. Eyeexamination is also essential since the tumor may cause pressure onto the opticnerve and cause visual changes.
Treatment for Pituitary Tumors
Treatment for pituitary tumors includes surgery,certain drugs and/ or radiation therapy. Patients are most commonly treatedsurgically. The goal of the surgery is removal of the entire tumor andpreservation of at least some of the normal pituitary gland.Prolactin-secreting tumors can be treated with specific drugs which reduceexcessive production of prolactin. Radiation therapy is administered afteroperation or in case the tumor is inoperable.
Hormonal replacement is indicated in all patientswho have undergone removal of the entire pituitary gland or in those pituitarygland does not function properly after radiation therapy.