SUN-LB047 Two Unusual Cases of Pituitary Tumors Presenting with Acromegaly

Introduction: Acromegaly is a rare pituitary disorder. Only seen 1-2 times in most endocrinologist careers. In one study, 0.6% of the cases of pituitary adenomas had pituitary gigantism. Most of what is known is from isolated case reports in the adult population. Over 95% of patients with acromegaly have a growth hormone secreting pituitary adenoma. Case 1: A 16-year-old female presented for evaluation of primary amenorrhea. Initiation of puberty was at 12. She was very tall for age. Mom reported a rapid growth after the age of 9. Her height was at the 95(th) percentile while her target height was at the 50(th) percentile. On exam, she had coarse facial features and large hands and feet. Initial evaluation revealed a serum prolactin of 8.5 ng/ml, LH 0.1 IU/L (L), free testosterone 2.1 ng/dl, total testosterone 10.01 ng/dl, GH 7.03 ng/ml (H), IGF-1 at 1162 ng/ml (H) and normal TFTs. Growth hormone suppression test confirmed growth hormone excess. The lowest growth hormone level was 4.1 ng/ml at 30 minutes after a 75 gm load of glucose. An MRI of the pituitary gland revealed a 1.9 x 1.3 x 1.3 cm lobular mass within the sella and suprasellar region, with some displacement of the pituitary stalk and optic chiasm. She successfully underwent transphenoidal resection of the pituitary mass. After surgery: She presented with DI post operatively that has resolved. Normal cortisol levels. She has secondary hypothyroidism and is on levothyroxine. IGF-1 started dropping 4 days post-op (738mg/ml) and normalized 2 months later (373 ng/ml) 22 months post op: cortisol and IGF-1 are normal. No evidence of DI. She remains on levothyroxine and is on an estradiol patch. Case 2: A 15-year-old girl presented for evaluation of irregular periods. On exam, she had coarse facial features, large hands and feet, acanthosis nigricans, hirsutism and a deep voice. Height was at the 50(th) percentile with MPH at the 25(th) percentile. Initial evaluation revealed a very elevated serum prolactin of 260 ng/dL. Serum LH was low at 0.14 mIU/ml, free testosterone was elevated at 5.6 pg/mL. She had mixed hyperlipidemia. TFTs were normal. Repeat labs confirmed hyperprolactinemia and she was started on carbergoline. Further evaluation revealed an elevated IGF-I level at 1374 ng/mL (208-619), elevated IGFBP-3 of 11.2 mg/L (3.4-9.5) with a normal cortisol and serum sodium. Growth hormone suppression test confirmed excessive growth hormone production with the lowest growth hormone level being 11.7 ng/mL 120 minutes after 75 gm load of glucose. An MRI of the pituitary gland revealed a pituitary macroadenoma measuring 1.7 x 1.5 x 2 cm invading into the cavernous sinus and wrapping around the ICA. She successfully underwent trans-sphenoidal resection of the pituitary mass and is post op. Conclusion: Acromegaly is rare in children and may present with unusual symptoms of other pituitary hormone dysfunction. Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.