Acromegaly with no pituitary adenoma and no evidence of ectopic source

More than 99% of patients with acromegaly harbor a growth hormone (GH) secreting pituitary adenoma. As the time from onset of signs/symptoms to diagnosis of acromegaly is long (symptom onset to diagnosis is often 4-10 years), pituitary adenomas that cause GH excess are often large and are nearly always visible on conventional magnetic resonance imaging (MRI). However, in rare circumstances, acromegalic patients without an ectopic source will not have imaging evidence of a pituitary adenoma. Management of these patients poses special challenge, and once ectopic source of GH/growth-hormone-releasing hormone (GHRH) is ruled out, an exploration of pituitary might be useful. We herein report a case of acromegaly with imaging evidence of sellar floor osteoma, but no pituitary adenoma, and negative work up for an ectopic source of GH/GHRH tumor, and on surgical exploration pituitary adenoma could be identified and removed and confirmed on histopathologic examination.