How should a pituitary adenoma, including a pituitary incidentaloma, initially be evaluated?
A thorough history and physical examination can detect symptoms and/or signs of pituitary hormone excess or hypopituitarism. Baseline pituitary hormone testing should include the following serum/plasma measurements: an a.m. cortisol, ACTH, prolactin (PRL), GH, insulin-like growth factor 1 (IGF-1), TSH, free thyroxine (free T 4 ), LH, FSH, testosterone (men), and estradiol (women). A dehydroepiandrosterone sulfate (DHEA-S) level is also helpful in assessing for possible central adrenal insufficiency because it is the earliest adrenal marker of deficiency. Additional screening tests for Cushing’s disease are recommended only if clinically indicated. In assessing for preoperative hypopituitarism, emphasis should be placed on diagnosing and replacing thyroid hormone and glucocorticoid deficiencies, as needed.