Pituitary Adenoma

A pituitary adenoma is a tumor that forms in the pituitary gland, which sits behind the nose and below the brain. Most pituitary adenomas are benign, meaning they are not cancerous, but they can still cause significant health problems by affecting hormone production or pressing on nearby structures such as the optic nerves.

Pituitary adenomas may be classified as functioning tumors, which produce excess hormones, or nonfunctioning tumors, which do not release hormones but may grow large enough to cause symptoms. Some tumors remain small and stable for years, while others require medical treatment or surgery.

Advanced care for pituitary tumors may include endoscopic pituitary surgery, radiosurgery or specialized skull base surgery.

Pituitary adenomas are categorized based on size and hormone activity.

Functioning pituitary adenomas

These tumors produce excess hormones and may lead to specific hormonal disorders, including:

• Prolactin-secreting tumors (prolactinomas)
• Growth hormone-producing tumors
• ACTH-producing tumors associated with Cushing’s disease
• TSH-producing tumors affecting thyroid function

Nonfunctioning pituitary adenomas

These tumors do not produce hormones but can grow large enough to compress nearby structures, including the optic nerves and normal pituitary tissue.

Microadenomas and macroadenomas

• Microadenomas measure less than 10 millimeters.
• Macroadenomas measure 10 millimeters or larger and are more likely to cause vision changes or headaches.

Symptoms vary depending on the size of the tumor and whether it affects hormone production.

Common symptoms may include:

• Frequent headaches
• Vision problems, especially loss of peripheral vision
• Fatigue or weakness
• Hormonal imbalances
• Unexplained weight changes
• Infertility
• Irregular menstrual cycles
• Erectile dysfunction
• Excessive growth of hands or feet
• Increased thirst or urination

Some pituitary adenomas are discovered incidentally during imaging for unrelated conditions such as headaches or neurologic evaluations.

The exact cause of most pituitary adenomas is unknown. Researchers believe that genetic changes in pituitary cells may contribute to abnormal growth.

Risk factors may include:

• Family history of endocrine tumors
• Certain inherited syndromes, such as multiple endocrine neoplasia type 1 (MEN1)
• Middle adulthood
• Previous pituitary abnormalities

Most pituitary adenomas occur without a clear inherited cause.

Diagnosing a pituitary adenoma typically involves a combination of imaging studies, hormone testing and neurologic evaluation.

Your care team may recommend:

• Magnetic resonance imaging (MRI) to visualize the pituitary gland
• Blood and urine tests to measure hormone levels
• Vision testing to assess optic nerve involvement
• Endocrine evaluations to identify hormone imbalances

Advanced imaging and multidisciplinary evaluations help determine whether minimally invasive approaches such as endoscopic pituitary surgery may be appropriate.

Treatment depends on the type, size and behavior of the tumor, as well as the symptoms it causes.

Options may include:

Observation and monitoring

Small tumors that do not cause symptoms may only require periodic imaging and hormone testing.

Medications

Certain hormone-producing tumors respond well to medications that reduce hormone levels or shrink the tumor.

Surgery

Surgery is often recommended for larger tumors or tumors causing vision changes. Many patients benefit from minimally invasive endoscopic pituitary surgery, which allows surgeons to access the tumor through the nasal passages without large incisions.

Some complex tumors may require advanced skull base surgery.

Radiation therapy

Focused radiation techniques such as radiosurgery may be used for tumors that cannot be completely removed or that return after surgery.

Without treatment, pituitary adenomas can lead to complications such as:

• Permanent vision loss
• Hormonal deficiencies
• Infertility
• Osteoporosis
• Cardiovascular complications
• Pituitary apoplexy (a sudden bleeding event within the tumor)

Prompt diagnosis and treatment can help reduce the risk of long-term complications.

There is no proven way to prevent pituitary adenomas. However, early evaluation of symptoms such as persistent headaches, hormonal changes or unexplained vision problems may help identify tumors before complications develop.

People with inherited endocrine disorders may benefit from regular medical monitoring and imaging.

If you are experiencing symptoms that may be related to a pituitary adenoma, Baptist Health Brain & Spine Care can help guide you through diagnosis and treatment. Our multidisciplinary team includes neurosurgeons, endocrinologists, neurologists and radiation specialists who work together to create personalized care plans.

To schedule a visit with a Baptist Health Brain & Spine Care provider, fill out an appointment request form or call 833-596-3876.