Common Treatments for Pituitary Tumors

The pituitary gland is a small gland located at the base of the brain (behind the upper part of the nose). The pituitary is known as the "master gland" since it regulates the secretion of most hormones in the body. Pituitary tumors are often noncancerous and grow slowly, and fortunately, the majority of these tumors are treatable.

Early intervention is ideal, especially if these tumors are causing troublesome symptoms. Pituitary tumors can be treated by surgical removal, radiation therapy, and/or medication therapy to shrink or eradicate the tumor.

In the majority of pituitary tumors, surgery remains the first line of treatment. Surgery is indicated to relieve mass effect or compression on the eye nerves and restore pituitary function or hormone secretion, reduce tumor size, and collect tumor samples for tissue analysis.

Pituitary tumors are surgically treated by either of two main approaches. The transnasal transsphenoidal method reaches the tumor through the nose and is popular because it is minimally invasive and efficient. The transcranial approach requires opening the skull to reach the tumor through a craniotomy and is very rarely, if ever, used. The transcranial approach is beneficial when the tumor is large, beyond the regular boundaries of the usual pituitary tumor, and cannot be sufficiently exposed through a minimally invasive procedure.

Interestingly, combining both strategies is also a viable option in rare cases. Each patient’s case is unique. Your surgeon should personalize your care to achieve the best possible outcomes.

The transnasal transsphenoidal approach involves inserting surgical instruments into the nostril and moving them along the nasal septum. There are two primary methods. The first uses an operating microscope, while the second uses an endoscopic camera.

When using a standard microscope, surgeons can directly visualize the surgical area and excise the tumor. Bimanual skill is critical in this circumstance to safeguard the essential structures encircling the tumor (i.e., blood vessels and nervous tissue). When the endoscopic approach is used, a tiny camera is placed through the nose, resulting in less normal tissue disruption.

In this approach, the patient is placed on the operating table, and the desired access route is cleansed and prepared. The most common entry points are on the forehead or the side of the head. Incisions typically follow natural skin creases and are located behind hairlines for best cosmesis.  

Upon creating the opening in the skull, the protective dura must be incised before reaching the brain. Once the brain has been exposed, it is gently moved to establish an access path to the pituitary gland. The tumor is located and carefully removed away from nearby structures. The surgeon will remove as much of the tumor as safely as possible and ensure that no blood is left behind before closing of the bony opening and incision.

A pituitary tumor can be treated with a variety of radiation therapy options. Radiation therapies for pituitary tumor include Intensity Modulated Radiation Therapy (IMRT), Stereotactic Radiosurgery (SRS), and proton beam radiation therapy. All three approaches involve precise energy beam targeting to focus only on the tumor while limiting damage to the surrounding healthy tissue. Most often, radiation is used when the remaining tumor after surgery has shown evidence of growth on imaging.

In IMRT, the radiation beams are aimed and shaped to the contours of the tumor using 3D technology. SRS involves focusing hundreds of radiation beams from different angles into a single core focus on the tumor. Each individual beam of SRS is weak, but when combined, they send a substantial quantity of energy to the tumor site. 

While SRS and IMRT use x-ray energy to kill tumor cells, proton beam radiation uses protons, which are less damaging to healthy tissue.

Tumor response to radiation therapy is variable and hard to predict. As assessed by tumor shrinkage or growth stoppage, benefits can take months or years to manifest. As a result, you'll need to have checkups every year to ensure the treatment is working. This frequently entails brain imaging and blood tests to measure hormone levels.

In certain cases, pituitary tumors can be treated with medications. In pituitary tumors that secrete the hormone prolactin (prolactinomas), medication alone is commonly used before other types of treatments.

Cabergoline and bromocriptine are the most common drugs used to treat these types of pituitary tumors. They work to reduce the size of a pituitary tumor and decrease excessive hormone secretion. Because of its favorable side effect profile and long-lasting effects, cabergoline is typically tried first. You'll need to take cabergoline twice a week for at least six months for the treatment of prolactinoma.

If a pituitary tumor is discovered incidentally (meaning that MRI was performed for reasons other than symptoms related to a pituitary tumor), it is often reasonable to monitor the tumor using periodic imaging (typically every year). Surgical intervention may not be needed. Your doctor will set up regular follow-up appointments to see if the tumor remains the same or progresses to the point where treatment is required. You may be able to stay in the monitoring stage for a long time without needing to make immediate treatment plans as pituitary tumors grow very slowly.

You'll probably have a follow-up appointment once a year to check on your pituitary tumor. This will involve an MRI scan to monitor the tumor's size, form, and other physical attributes, as well as blood testing to follow potential changes in hormone levels that could contribute to the development of new symptoms. Slight variations between tests may not necessitate commencement of medication, radiation, or surgery.

Pituitary tumors can be treated and managed in a variety of ways, including observation, surgery, medications, and/or radiotherapy. Your doctor will discuss treatment options with you. Take your time to consider your options and evaluate the advantages of each against its potential risks and adverse effects.

• Pituitary tumors are most often treatable.
• Some pituitary tumors require no intervention and can be observed via periodic imaging.
• Surgery remains the first line of treatment for most pituitary tumors.
• Some pituitary tumors (prolactinomas) can be treated with medication alone.
• Pituitary tumors can be reduced via radiation therapy.

• Pituitary Network Association 
• National Brain Tumor Society
• American Brain Tumor Association 
• Pediatric Brain Tumor Foundation
• Endocrine Society 
• Pituitary Foundation 
• Cushing’s Support & Research Foundation