Benign tumors of the pituitary gland are extremely common, occurring in about one in five people. Most of these tumors do not cause any problems or symptoms, and therefore a large number are never even diagnosed. But for those that are, Memorial Sloan Kettering Cancer Center’s Pituitary Tumor Center was established to treat patients in a specialized, multidisciplinary fashion.
The Pituitary Tumor Center was established in 2007 by Viviane Tabar, a researcher and neurosurgeon who understood that, despite being a cancer center, Memorial Sloan Kettering also had a unique capability for treating benign pituitary tumors, also known as adenomas. Before the center was created, Memorial Sloan Kettering had treated only three or four cases of pituitary adenoma each year, usually in patients who already were being treated for some type of cancer. Now Memorial Sloan Kettering sees about 200 patients with pituitary tumors each year, with most of those tumors being benign.
The pituitary gland synthesizes and secretes hormones that are key to how the body functions. Its activity is controlled by the part of the brain called the hypothalamus, which serves as the connection between the nervous system and the endocrine system. Pituitary tumor cells often are able to carry out the function of healthy pituitary cells, meaning that they can make and secrete additional amounts of hormones such as growth hormone and cortisol. Thus, symptoms of pituitary tumors are often related to endocrine disruptions and include gigantism, changes in the voice, sleeping problems, and, in younger women, problems with menstruation or fertility. The tumors can also block the production of hormones, leading to other endocrinological problems.
Another symptom of a pituitary adenoma is tunnel vision, because the gland is located adjacent to the optic chiasm, the part of the brain where the optic nerves cross. But the majority of patients never experience any symptoms, and their tumors are found incidentally, while receiving scans for unrelated medical conditions, such as headaches. This is becoming increasingly common as the use of diagnostic MRIs increases.
(Left) An MRI shows the location of a pituitary gland tumor before surgery. (Right) An intraoperative MRI shows the same area after the tumor has been removed.
One of the most important aspects of the Pituitary Tumor Center is its multidisciplinary nature. Patients who visit the center are often able to see three specialists — a surgeon, an endocrinologist, and an ophthalmologist — on the same day. “Traditionally, tests for patients with these tumors had to be done by several different doctors and required multiple referrals, and it could often take months for patients to receive a recommendation on what kind of treatment they should have,” Dr. Tabar explained. “Whenever possible, our patients are able to receive all the services they need at the same time, which is especially important for patients traveling from out of state or internationally.”
Dr. Tabar’s personal interest in treating adenomas led to the creation of the new center. “I wanted to establish this center in part because I had a particular interest in the technical aspects of the surgery,” Dr. Tabar said. “Because the pituitary gland is at the base of the brain, you perform the surgery through the nose rather than going through the skull. This can make the procedure very challenging. In addition, there have been significant technological advances over the past few years, which make it much safer.”
An important advance has been the use of intraoperative MRI, which allows surgeons to continually create new images of the pituitary gland and surrounding structures as surgery is being performed. “We are the only center in the United States doing pituitary surgery routinely in the MRI suite,” Dr. Tabar said. “What this gives us is the ability to look for very small amounts of residual tumor while avoiding delicate structures nearby, such as the optic nerves and the carotid arteries. Also, when you remove the tumor, there is a significant shift in the topography of the brain: The gland’s position changes. It’s important to remove as much tumor as possible while preserving the gland itself, so that patients are not committed to a lifetime of needing hormone therapy.”
She added that because the tumors are benign, the majority of patients live a long time after they receive treatment. “Because their life expectancy is long, their quality of life after treatment is paramount,” she said. In addition to surgery, some patients require radiation therapy to remove remaining tumor and some also need ongoing hormonal therapy.
The other members of the Pituitary Tumor Center are Monica Girotra, an endocrinologist; Kathryn Beal, a radiation oncologist; and Erik Kobylarz, a neuro-ophthalmologist who is affiliated with Weill Cornell Medical College. The members of the team meet regularly, along with their nurses, to ensure that the unique issues of their patients are addressed. To further simplify the process for patients, a single phone line was established for patients to schedule appointments with all the doctors in the center. Please call 212-639-3935 for an appointment or visit www.mskcc.org/pituitarytumors.