- UTHealth Houston Skull Base Program
- Pituitary Adenomas
Pituitary Adenomas
What are pituitary adenomas?
Pituitary adenomas are typically benign tumors that develop in the pituitary gland, a small yet critical structure at the base of the brain that regulates hormone production throughout the body. These tumors are relatively common and are classified based on whether they produce hormones (functional) or do not (nonfunctional). Although usually noncancerous, pituitary adenomas can affect vision, hormone balance, and overall health due to their location near the optic nerves and other important structures.
What causes pituitary adenomas?
The exact cause of most pituitary adenomas is unknown. In rare cases, they are associated with inherited genetic conditions, including multiple endocrine neoplasia type 1, called MEN1. Most cases occur sporadically without a clear risk factor. There are no well-established lifestyle or environmental causes.
Symptoms
Symptoms vary depending on the size of the tumor and whether it secretes hormones. Functional adenomas may cause hormone-related conditions, such as excess prolactin that can lead to irregular menstrual cycles or infertility, excess growth hormone that can cause acromegaly, or excess ACTH that can lead to Cushing’s disease. Nonfunctional tumors often present due to headaches, vision changes—especially loss of peripheral vision—and, in some cases, fatigue or hormonal deficiencies caused by compression of the normal pituitary gland.
How are pituitary adenomas diagnosis?
Diagnosis typically involves imaging studies, most commonly MRI of the brain, to visualize the tumor and assess its size and impact on surrounding structures. Blood tests are essential to evaluate hormone levels and determine whether the tumor is functional. Vision testing may also be performed to assess any impact on the optic nerves.
How are pituitary adenomas treated?
Treatment depends on the type of tumor, its size, and its effects on hormone production and surrounding structures. Many functional adenomas, particularly prolactin-secreting tumors, can be effectively treated with medication. Surgery, which is most often performed using a minimally invasive endoscopic approach, is commonly recommended for tumors causing vision problems or those that do not respond to medical therapy. Radiation therapy may be used in selected cases, particularly for residual or recurrent tumors.
Most pituitary adenomas have an excellent prognosis with appropriate treatment. Recovery depends on the treatment approach and the extent of the tumor. Hormone levels often improve after treatment, although some patients may require long-term hormone replacement therapy. Regular follow-up with imaging and endocrine evaluation is important to monitor for recurrence or ongoing hormonal changes.