From the Guidelines
Laboratory Tests for Pituitary Mass Follow-up
Baseline laboratory tests for follow-up of a pituitary mass should include evaluation of ACTH, cortisol, TSH, free T4, and electrolytes.
- Additional tests may be considered based on clinical presentation, such as:
- LH and testosterone in males
- FSH and estrogen in premenopausal females with symptoms like fatigue, loss of libido, mood changes, or oligomenorrhea
- Standard-dose ACTH stimulation testing for indeterminate results (AM cortisol < 3 mg/dL and < 15 mg/dL) 1
- MRI brain with pituitary or sellar cuts is recommended for all patients with new hormonal deficiencies, particularly those with multiple endocrine abnormalities, severe headaches, or complaints of vision changes 1
- Thyroid function tests and regular MRI surveillance are suggested for disease monitoring in patients with confirmed TSHomas, although the optimal surveillance schedule is unknown and should be individualized 1
- Pituitary hormone assessment should be undertaken as indicated clinically to confirm the absence of pituitary hormone excess from a functioning adenoma or the presence of hormone deficiency 1
- Visual acuity and visual fields assessment is mandated in cases of suspected visual deterioration, which is a well-described presentation of non-functioning pituitary macroadenoma (NFPA) in children and young people (CYP) 1
From the Research
Laboratory Tests for Pituitary Mass Follow-up
The following laboratory tests are indicated for the follow-up of a pituitary mass:
- Serum prolactin levels for small tumors 2
- Laboratory evaluation for metabolic problems, such as thyroid and adrenal function 2, 3
- Insulin-like growth factor 1 (IGF-1) and growth hormone levels for growth hormone-secreting tumors 4, 5
- Late-night salivary cortisol level for adrenocorticotropic hormone (ACTH)-secreting tumors 4
- Thyroid-stimulating hormone (TSH) levels for TSH-secreting tumors 4, 5
- Gonadal, thyroid, and adrenal function tests for all patients with pituitary tumors 3
Additional Evaluations
Additional evaluations that may be necessary for the follow-up of a pituitary mass include:
- Ophthalmological examination, including formal visual field testing, for patients with tumors compressing the optic chiasm 5, 2, 6
- Imaging procedures, such as magnetic resonance imaging (MRI), to determine the presence, size, and extent of the lesion 3, 6
- Stimulation and suppression tests for pituitary hormones in selected situations 3
Specific Tumor Types
For specific types of pituitary tumors, the following laboratory tests and evaluations may be indicated:
- Prolactinomas: serum prolactin levels, dopamine agonist therapy 4, 5, 3
- Growth hormone-secreting tumors: IGF-1 and growth hormone levels, somatostatin analogues, pegvisomant 4, 5, 3
- ACTH-secreting tumors: late-night salivary cortisol level, petrosal sinus sampling for ACTH, adrenal steroidogenesis inhibitors 4, 3
- TSH-secreting tumors: TSH levels, somatostatin analogues 4, 5