Form, Function and Location: The Triple Threat of Pituitary Tumors

Contact Information
 
(608) 263-7502
 
UW Health Services
 
MADISON - The pituitary lies at a busy crossroads of the human brain. Sitting behind the eyes and nose, flanked by the carotid arteries, surrounded by important nerves controlling vision and facial sensation, and nestled next to the brain, this tiny gland has the potential to cause significant trouble.
 
The pituitary is also called the "master gland" because it secretes hormones that direct many other glands in maintaining normal metabolism and salt/water balance in the body.

"It's a critical bit of real estate," says UW Health neurosurgeon John Kuo, MD, PhD. "A half-centimeter pituitary tumor can affect the entire body."

Though pituitary tumors are often benign, their location in the brain and the vital role of the pituitary gland in the endocrine system call for specialized care. For that reason, Dr. Kuo formed the UW Health Multidisciplinary Pituitary Tumor Clinic, bringing together specialists from neurosurgery, endocrinology, radiation oncology, neuro-ophthamology, neuroradiology and neuropathology to provide a comprehensive range of services to patients.

Dr. Kuo says their team-based focus allows for more comprehensive management plans to address the myriad symptoms caused by pituitary tumors.

"All too often, a patient's presenting symptoms are thought to be unrelated to the pituitary and are treated in isolation, but the tumor is still there, and growing," Dr. Kuo says. "That's where this multi-disciplinary approach becomes so necessary and effective."

Early indicators possibly related to pituitary tumors include menstrual irregularities or infertility for women, decreased libido for men, markedly lower energy level or excessive weight gain, headaches and blurriness or loss of peripheral vision. Once diagnosed, treatment plans are developed to deal with both the tumor and its ripple effects on the body. Plans may include surgery, medications, and/or radiation therapy.

The pituitary's unique location does have one advantage: it can be reached by using a minimally invasive endonasal transsphenoidal craniotomy. Dr. Kuo is specially trained to use computer navigational guidance with microscopic and endoscopic visualization to quickly and effectively remove many pituitary tumors, usually with only a three-day hospital admission. When needed, advanced open-skull base surgical techniques are combined with the trans-sphenoidal craniotomy to remove excessively large pituitary tumors.

"Many patients are pleasantly surprised that they end up with little more than a swollen nose the day after this procedure," Dr. Kuo says.

Other therapeutic options to compliment surgery and/or medications include stereotactic radiosurgery and fractionated stereotactic radiotherapy, guided by the precise integrated imaging of TomoTherapy, invented at the University of Wisconsin-Madison.

The effects of the tumor's physical presence in the brain - headaches and vision problems - can be treated and even reversed by removing or reducing the tumor. The effect of the tumor's chemical presence in the brain, on hormone production and regulation, can result in endocrine problems such as infertility, hyperprolactinemia, Cushing's disease or acromegaly. Patients may be initially diagnosed with diabetes, hypertension or carpal tunnel syndrome due to the systemic effects of pituitary tumors.

Clinic endocrinologists work to alleviate or reverse the effects of these disorders through careful medication management. Postoperative management of permanent changes in endocrine function is also essential to avoid "endocrinopathy" - the long term deleterious effects of a pituitary tumor on a patient's health.

Dr. Kuo cautions that pituitary tumors can recur even many years after initial therapy. If detected when still small, recurrent pituitary tumors can be treated non-invasively with outpatient radiation therapy.

"The operating microscope and endoscope are used to remove tumor tissue, but we cannot see individual cells," Dr. Kuo says. "One missed cell is all it takes for tumor recurrence. After surgery, patients will need regular clinic visits and surveillance MRIs. I tell my patients, 'You've got me for life.'"

Dr. Kuo began the UW Health Pituitary Tumor Clinic in September 2006, modeling it after similar programs at the University of Southern California and the University of Virginia. This interdisciplinary collaboration of UW brain tumor specialists participating in international brain tumor research consortiums also allows clinic patients to participate in advanced clinical trials for new breakthroughs in treatment and care as needed.

In addition to the twice-monthly clinic, Dr. Kuo and his colleagues offer an e-consult service, which allows referring physicians and patients to send records for preview to determine if the clinic is appropriate for their patients. Appointment slots are held for new patients with immediate needs.

"Pituitary tumors are often undiagnosed - they're probably more common than we realize," Dr. Kuo says. "I hear family physicians say they might see one brain tumor in an entire year. They're probably seeing many more."

Appointments at the UW Health Pituitary Tumor Clinic require a physician referral. To schedule, please call (608) 263-7502. To use the e-consult service, contact the Pituitary Tumor Clinic Coordinator at (608) 265-6358.
 
Date published: 4/28/2008