Pituitary Tumors

The pituitary gland is located at the base of the brain and is involved in the secretion of several hormones. Tumors arising from the pituitary gland are called adenomas – “adeno” means gland and “oma” means tumor. Adenomas are benign and slow growing. These tumors are classified as “secreting” tumors or “non-secreting.” The majority are secreting tumors and are classified further by the hormone(s) being secreted. An MRI scan is used to determine tumor size and position in relation to other brain structures. Several blood tests can determine which hormones are elevated or reduced. 

Symptoms

Symptoms are caused by the growing tumor pushing on surrounding structures, or by the production of too much or too little hormone.

Prolactinoma - These tumors cause over-production of prolactin. In women it may cause inappropriate production of breast milk, or it may cause menstruation to stop. In men, it may cause decreased sex drive and impotence.

ACTH Producing Adenomas - ACTH stimulates the adrenal gland to make and secrete natural steroids. Excess glucorticosteroids (natural steroids) cause Cushing’s disease. Symptoms include moon-shaped face, excess hair growth, easy bruising, high blood pressure, and menstrual irregularities.

Growth Hormone Producing Adenomas -  These tumors may cause gigantism in children and adolescents. In adults, the hands, feet and lower jaw become enlarged.

Other Hyper-secreting Pituitary Tumors -  They include tumors which excrete excess hydrotropic (thyroid stimulating hormone), follicle stimulating/luteinizing hormone (controls ovaries and testes), and alpha subunit (a glyco-protein hormone).

Non-secreting Tumors -  These tumors grow slowly. If they expand enough, they may press on the optic nerves causing vision disorders and headaches. If the tumors compress the pituitary gland itself so that it cannot produce and deliver normal hormones, hypopiuitarism develops. Hypopituitarism can have symptoms such as weakness, fatigue, loss of sexual function, a pale complexion, and apathy.

Treatment

Treatments depend on size, location and hormonal activity of the tumor. Presence of visual problems and the age and overall health of the person will also affect treatment. Treatments include surgery, drug therapy, and radiation, alone or in combination.

The most common type of surgery involves removal of the tumor through the nose and sinuses – “transphenoidal approach.” Less often, a craniotomy during which a portion of the skull is removed to gain access to the pituitary gland is necessary. Radiation therapy is used for a persistent or recurrent tumor. Drug therapy depends on the hormone function of the tumor.