Acromegaly caused by a growth hormone-releasing hormone-secreting carcinoid tumor: case report

We describe a patient with acromegaly and pituitary hyperplasia secondary to a growth hormone-releasing hormone-secreting gastrointestinal carcinoid tumor. This case report illustrates the importance of including this rare clinical syndrome in the differential diagnosis of acromegaly for patients with suspected or known neuroendocrine tumors.

A 19-year-old, Asian-American, male patient with a 2-year history of a nonresectable, metastatic, intestinal carcinoid tumor presented with complaints of headaches, arthralgias, sweats, and changing features. The examination revealed a young subject with acromegalic features, without visual field deficits. Magnetic resonance imaging revealed a diffuse sellar mass that extended suprasellarly to compress the optic chiasm. Endocrinological studies demonstrated a growth hormone level of more than 100 ng/ml and an inappropriately elevated growth hormone-releasing hormone level.

The patient underwent transsphenoidal resection of the pituitary mass for diagnostic and decompressive purposes. The pathological examination revealed pituitary hyperplasia, without evidence of an adenoma. Therapy with long-acting repeatable octreotide (Sandostatin LAR; Novartis AG, Basel, Switzerland) was initiated postoperatively, to further control the acromegaly and carcinoid tumor. The soft-tissue swelling resolved, and the patient remained free of headaches, arthralgias, and sweats at the 6-month follow-up examination.

Ectopic acromegaly is a rare syndrome that must be recognized by neurosurgeons because its treatment differs from that of classic pituitary acromegaly. We describe a patient for whom this syndrome was documented with magnetic resonance imaging, endocrinological testing, and pathological examinations.