Neurosurgery Procedure Curbs Growth of Pituitary Tumors

Neurosurgical Procedure Helps Curb Growth of Pituitary Tumors

SAN FRANCISCO (April 10, 2000) - Gamma knife radiosurgery is a novel approach to the treatment of pituitary tumors and key to preventing future tumor growth, according to a recent study examining the safety and efficacy of radiosurgery as a treatment for pituitary tumors. Lawrence S. Chin, MD, a neurosurgeon at the University of Maryland Medical Center, will report on the findings of this study at the 68th Annual Meeting of the American Association of Neurological Surgeons, on Wednesday, April 12, 2000.

Pituitary tumors are generally non-aggressive, non-cancerous and non-metastatic (meaning that they do not spread to other parts of the body). They usually manifest themselves as growths on or within the pituitary gland - a small, kidney bean-shaped structure attached to the base of the brain and responsible for controlling and coordinating: 1) growth and development; 2) the function of various body organs (i.e. kidneys, breasts and uterus); and 3) the function of other glands (i.e. thyroid, gonads and adrenal glands). Pituitary tumors are very common and represent 10 to15 percent of all intracranial tumors.

In this study, 29 patients with pituitary adenomas (benign tumors that arise exclusively in the anterior pituitary) were treated with Gamma Knife irradiation. Of those, 26 had undergone previous surgery and several had received conventional radiotherapy treatments to eradicate the tumor.

Following the Gamma Knife treatment, 28 of the patients demonstrated an improvement, thereby suggesting that radiosurgery is a safe and effective means of controlling residual or recurring tumor after surgical resection.

"Gamma Knife surgery is not intended to replace more traditional surgical treatments for tumor eradication," said Dr. Chin. "It is, however, designed to prevent the future growth of tumors. In fact, our findings indicate that Gamma Knife surgery for pituitary tumors is most effective following conventional surgery or in patients with persistent endocrinological abnormalities."

The Gamma Knife is a non-invasive neurosurgical tool designed to minimize the effects of radiation by sending multiple radiation beams to converge on one target point. The helmet-like device is worn by the patient and has 201 round holes in it, which aim a single, high dose of Gamma Knife radiation at the targeted tissue. The treatment is done in a single sitting and results in increased biological efficacy with decreased hospital stay and side effects.

"Although Gamma Knife surgery is ideally suited as an adjunct to the traditional transphennoidal surgery, it also may be useful for patients medically unfit for surgery and beneficial for those patients who cannot be cured by surgery," added Dr. Chin. "It arms the neurosurgeon with more treatment options and opens up a window of opportunity for future studies in this area."

Founded in 1931 as the Harvey Cushing Society, the American Association of Neurological Surgeons (AANS) is a scientific and educational association with nearly 5,500 members worldwide. The AANS is dedicated to advancing the specialty of neurological surgery in order to provide the highest quality of neurosurgical care to the public. All active members of the AANS are Board-certified by the American Board of Neurological Surgery. Neurosurgery is the medical specialty concerned with the prevention, diagnosis, treatment and rehabilitation of disorders that affect the spine, brain, nervous system and peripheral nerves.

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Media Representatives: The Annual Meeting press kit can be found in the Media Center Section of the AANS Web site at: http://www.neurosurgery.org/aans.

If you would like to cover the meeting or interview a neurosurgeon - either on-site or via telephone - please contact an AANS Public Relations representative at (847) 692-9500 or call the Annual Meeting Press Room beginning Sunday, April 9 at (415) 978-3715 (3716).

To view a special presentation on Gamma Knife Radiosurgery, visit http://www.neurosurgery.org/pubpages/whatis/radiosurgery.html.