CushieBlog

Double pituitary adenomas with growth hormone (GH) and adrenocorticotropic hormone (ACTH) secretion are very rare. They are responsible for acromegaly with hypercortisolism. Subclinical corticotropic adenomas are exceptional.

Herein, we report the case of a patient with double functional pituitary adenomas causing acromegaly and subclinical Cushing’s disease. A 45-year-old woman was referred to our Department for suspected acromegaly. Her past medical history included diabetes mellitus treated with oral antidiabetic drugs and hypertension.

On physical examination, she had a large prominent forehead, thickened lips, increased interdental spacing, prognathism, and enlarged hands and feet. No signs of hypercortisolism were found. Biological investigations showed an elevated insulin growth factor-1 (IGF-1) level at 555 ng/mL, a GH nadir after 75 g oral glucose tolerance test at 2 ng/mL, a morning cortisol level at 158 ng/mL, an ACTH level at 64 pg/mL, a thyroid stimulating hormone (TSH) level at 2.26 mIU/L, and a free thyroxine (FT4) level at 12.8 pmol/L. Cortisol level after low-dose dexamethasone suppression test was 86 ng/mL.

The diagnosis of acromegaly associated with Cushing’s disease was established. Pituitary magnetic resonance imaging showed a pituitary macroadenoma with no clear limits. The patient underwent transsphenoidal tumor resection. The pathological examination revealed two separate pituitary adenomas. The positivity to ACTH and GH was 100% and 80%, respectively.

This case emphasizes the necessity of an evaluation of all the pituitary axes in case of adenoma in order not to miss a double hormonal secretion or more even in the absence of suggestive clinical signs.