Our Approach & Expertise
Our Intra-Operative Imaging Suite View a slide show of our intra-operative imaging suite equipped with a MRI scanner 
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Our multidisciplinary approach to the treatment of these tumors allows neurosurgeons, endocrinologists, neuro-ophthalmologists, skull base surgeons, radiation oncologists, and neuroradiologists to work together as they devise an individualized treatment plan for each patient. State-of-the-art diagnostics -- including imaging, hormone testing, and visual field testing -- combined with surgery, radiation therapy, and medication are used to ensure that patients receive the most sophisticated care available.
Advanced Imaging Technology
Tumors of the pituitary gland are often difficult to diagnose, and some go undetected for a person's entire lifetime. Many of these tumors never cause symptoms and are only discovered through imaging studies conducted for an unrelated health issue. Others cause a range of symptoms -- such as headaches, nausea, and vision problems -- that can be attributed to other diseases, so the diagnosis of a pituitary tumor is often overlooked.
At Memorial Sloan-Kettering, where MRI is used regularly to diagnose and monitor tumor growth, we have special expertise in the use of this technology to diagnose such tumors. MRI is the best imaging technique for pituitary tumors because the technology can identify even the tiniest tumors -- including microadenomas, small pituitary tumors less than one centimeter (nearly 1/2 inch) in size. Contrast-enhanced MRI scans have become particularly useful in making accurate diagnoses of all types of brain tumors, including those in the pituitary gland. CT (computed tomography) is also used to find pituitary tumors, but less commonly than MRI.
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Intra-Operative Imaging Suite
Memorial Sloan-Kettering is one of a few hospitals in the country that has an intra-operative imaging suite equipped with a high-field strength magnetic resonance imaging (MRI) scanner in the operating room. Performing pituitary tumor surgery in this setting allows the neurosurgeon to reevaluate the tumor with MRI during the operation, thus enabling him or her to operate with increased precision and reducing the need for a second surgery.
Dynamic Pituitary Testing
The pituitary gland is often called the "master control gland" because it regulates the activity and function of most other glands in the body. The primary hormones produced by the pituitary gland are adrenocorticotropic hormone, growth hormone, prolactin, thyroid-stimulating hormone, follicle-stimulating hormone, and luteinizing hormone. (For information on each hormone's role within the body, visit the Overview.)
To determine if the pituitary gland is functioning correctly, hormones produced by the pituitary gland itself are measured. This is a complicated process in which hormones are assessed using a variety of tests that add, block, or remove hormones. This is known as "dynamic pituitary testing." Our endocrinologists perform these tests to aid in diagnosis as well as to measure pituitary function before and after surgery. The tests can also help physicians devise a plan of treatment. Treatment depends upon whether the tumor is functional and, if so, which hormone is secreted. It may include surgery, medication, and radiation therapy, either alone or in combination.
One important function of the pituitary gland is the ability to secrete, or release, excess hormones in times of stress when the body needs it the most. Examples of this are when the body is fighting infection or when a person needs to elevate his or her blood pressure quickly. This function is called "reserve capacity." Determining the pituitary gland's reserve capacity for specific hormones is one of the main reasons for performing dynamic pituitary testing.
Vision and Pituitary Tumors
The pituitary gland is located at the base of the brain near the nerves that carry signals from the eyes to the brain (called optic nerves). Any growth in the pituitary puts pressure on the surrounding areas and specifically on a part of the brain called the "optic chiasm." This is an "X" that is created from the two nerves that lead, one from each eye, to the opposite side of the brain. Compression of the optic nerves, or chiasm, can result in a change in one's vision.
Having a problem with one's visual field -- which includes both central and peripheral (or side) vision -- can sometimes mean that a patient has a disorder involving the optic nerves and brain. Such symptoms may be a sign of a tumor in the pituitary gland. Although change in a person's visual field usually develops very slowly, even the smallest change should be taken seriously.
Our ophthalmologists and neuro-ophthalmologists are skilled in performing and interpreting the results of visual field testing, a term that encompasses several different vision tests. These tests can detect the location and extent of vision loss and can be helpful in both diagnosis and treatment. Visual field testing can also help to monitor if the disease has progressed and evaluate treatment effectiveness.
Our Surgical Expertise
The primary treatment of most pituitary tumors is by means of surgery. The surgical approach depends on the type of tumor, its location, size, and whether it has spread into nearby tissues. Our neurosurgeons often use a minimally invasive technique called "transphenoidal hypophysectomy." In this procedure, the neurosurgeon removes the tumor through an incision in the nasal passage. Advantages of this approach are that no other part of the brain is touched, the neurologic complication rate is very low, and there is no visible scar following the procedure. A disadvantage of the technique is that it is difficult to remove large tumors using this method.
Recently, Memorial Sloan-Kettering neurosurgeons have been using a minimally invasive surgical procedure called endoscopy to remove pituitary tumors. This procedure employs a thin, lighted tube with a camera on its tip (called an endoscope) to allow the neurosurgeon to see into the back of the nasal septum without having to make an incision under the upper lip or the front part of the nasal septum. Special surgical instruments are threaded through the endoscope, and the sphenoid sinus is opened to reach the pituitary gland. The neurosurgeon can then access and remove the tumor.
While endoscopy takes less time than other surgical options and causes fewer complications, its use is limited by tumor size and location, and also by the shape of the sphenoid sinus.
In cases where the tumor is too large to be removed through either of these approaches, the surgeon performs a craniotomy, in which the tumor is removed through an incision in the front of the skull.
