Accurately assessing & treating hormonal deficiencies is an essential part of pituitary tumor therapy
Because pituitary adenomas and related tumors and cysts often impact hormonal health, diagnosing and treating such hormonal deficiencies and/or hormonal excesses is a core goal of therapy. Our pituitary endocrinologists and neurosurgeons have extensive experience working together to:
- Determine if a hormonal deficiency or excess is present
- Effectively manage and correct these abnormalities
Pituitary Gland & Pituitary Tumors
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The evaluation of pituitary gland function typically involves blood tests and in some instances, urine and saliva collections. Given the complexity of assessing pituitary gland function, it should typically be overseen by an endocrinologist.
In a patient with a pituitary-related tumor, an initial complete pituitary hormonal assessment is typically performed that includes the following tests:
- Adrenal axis: ACTH, cortisol
- Gonadal axis: LH, FSH, testosterone (in men), estradiol (in women)
- Growth hormone axis: GH, IGF-1
- Lactotroph axis: prolactin
- Thyroid axis: TSH, T4, free T4
- Urine specific gravity (to assess for urine concentration and for possible diabetes insipidus)
These tests assess for under or over-production of pituitary hormones and are essential in diagnosing pituitary gland failure which may involve one or multiple hormones such as low testosterone or low thyroid levels. They are also used to diagnose hormone-secreting tumors such as those causing acromegaly (excess GH) or prolactinomas (excess prolactin). In some patients, more sophisticated stimulation tests are indicated for assessing the pituitary gland’s ability to respond to hypothalamic hormones or other stimuli such as glucose. In patients being evaluated for possible Cushing’s syndrome or Cushing’s disease, collections of urine and salivary cortisol levels are often required to confirm a diagnosis.
For patients with pituitary adenomas, hormonal function typically improves or recovers after surgical removal, while in only a small minority it worsens. As shown in a publication from our group in 2008, studying over 440 patients, new hormonal deficiencies developed in 5% after surgery and was was most common in tumors 2 cm or greater in size.
In patients with craniopharyngiomas, pituitary hormonal deficiencies are significantly more common than in patients with pituitary adenomas, both before and after surgery, and there is a higher risk of permanent diabetes insipidus. As shown in another publication from our group in 2008, new pituitary gland deficiencies after surgery were lower in patients with Rathke’s cleft cysts and tuberculum sellae meningiomas.
Whether one needs temporary hormone replacement (for a few days or weeks after pituitary surgery) or life-long hormone replacement is very patient-specific and depends upon the tumor and the treatment given. The most commonly replaced hormones that are required for a pituitary hormonal deficiency are for low cortisol (typically given as hydrocortisone or prednisone), low thyroxin (typically given as levothyroxin) and low testosterone in men (typically given as a daily patch or gel or as an injection every few weeks). Some adult patients may also benefit from growth hormone replacement.
It is important that patients with pituitary hormonal deficiencies, have long-term follow-up with their endocrinologist as gland function can change, either improving or deteriorating over time. Patients who undergo radiosurgery or radiotherapy to the pituitary region are at particular risk of long-term decline in gland function over 5-10 years after radiation treatment.