Acromegaly with No Evidence of Pituitary Adenoma or Ectopic Source

Acromegaly is caused by the uncontrolled hypersecretion of growth hormone (GH) and secondary increases of insulin-like growth factor-1. More than 5% of patients with acromegaly have a growth hormone-secreting pituitary adenoma. Ectopic GH or growth hormone releasing hormone (GHRH)-secreting tumors are rare cause of acromegaly. Pituitary adenomas that cause the hypersecretion of GH are nearly always visible on magnetic resonance imaging. Rarely, patients without an ectopic source may have normal pituitary imaging. In managing this rare circumstance, exploring pituitary or medical treatment with a somatostatin analog might be useful. We describe a patient with acromegaly with no pituitary adenoma and no evidence of ectopic source, who was treated with long-acting octreotide.