Endocrine Abstracts

Introduction: Adrenal myelolipomas are rare benign tumors. There has been an association of adrenal myelolipomas with other pathologies with hormonal hypersecretion, such as hypersecretion of adrenocortical hormone (ACTH) in Cushing’s Disease and Congenital adrenal hyperplasia. We report a case of acromegaly with co-existent large adrenal myelolipoma.

Case Report: A 48-year-old caucasian male was referred to our Endocrinology consultation for an adrenal incidentaloma. His past medical history was relevant for dyslipidemia, with no medication. He was asymptomatic. On examination, his blood pressure was within normal range and there were no alterations compatible with acromegaly. His previous CT scans revealed a mass in the right adrenal gland that had grown from 40×44 mm to 59×51 mm in 2 years. An adrenal CT scan in our institution described the mass as a myelolipoma with 50×65×69 mm. The analytical studies revealed a negative 1 mg dexamethasone suppression test (0.6 μcg/dl), no elevation in 24 h urinary metanephrines (64.72 μcg/24 h) or normetanephrines (269.98 μcg/24 h), and a normal ionogram (Na 142 mEq/l, K 4.0 mEq/l, Cl 104 mEq/l) with no hypertension history. During the follow-up, the patient suffered a cranial trauma, and a pituitary adenoma was identified in a CT scan. Further analytical studies revealed an elevated IGF-1 (387 ng/ml), normal prolactin levels (4.5ng/ml), and normal thyroid function (TSH 0.92 μUI/ml, fT4 1.03 ng/dl). A pituitary MRI confirmed the presence of an adenoma with 10mm. An Oral glucose tolerance test confirmed the diagnosis of acromegaly, with a nadir of 1.39 ng/ml. The patient is currently awaiting pituitary surgery.

Conclusion: There is evidence that acromegaly is associated with increased incidence of several types of tumors, including colon polyps and thyroid nodules. To our knowledge, there are no reported cases in literature of large adrenal myelolipomas in patients with acromegaly. Our patient presented with a large myelolipoma, with no known etiology, and further studies and case reports are needed to ascertain their correlation.