Endocrine Abstracts

Introduction: Adrenal schwannoma is an extremely uncommon cause of incidentaloma. It originates from neural sheath Schwann cells of the adrenal gland. Herein, we report a case of left adrenal schwannoma that could not be diagnosed preoperatively.

Case report: A 53 years old female morbid obese (BMI: 66.68 kg/m²) patient was referred to endocrinology policlinic because of 5 cm left adrenal mass detected on abdominal screening while preparing patient to bariatric surgery. In patients medical history she has been diagnosed with obesity, hypertension and type 2 diabetes mellitus for 8 years. She was using oral antidiabetics, zofenopril and alpha receptor antogonist for hypertension. We ceased zofenopril treatment before testing function of adrenal mass. Plasma renin activity, serum potassium, aldosterone, cortisol (11.2 μg/dl, normal range: 6.2–19.4), dopamin, and 24 h urine fractionated metanephrines levels were in normal ranges, but in 1 mg dexametasone suppression test patients’ serum cortisol level was 2.23 μg/dl. We decided to left laparoscopic adrenalectomy because of mass size and subclinical Cushing syndrome. In histopathological examination of material obtained by surgical excision reported 4.5 cm adrenocortical adenoma contained myelolipomatous metaplasia and 3 mm adrenal schwannoma. After surgery, we found a suppressed cortisol level (0.58 μg/dl) with 1 mg dexametasone suppression test.

Discussion: A schwannoma in the adrenal gland is very rare and typically originates from the adrenal medulla. The low incidence and asymptomatic nature of the disease with no hormonal production make a definitive diagnosis of schwannoma in the adrenal region difficult leading to misinterpretation of the mass as an adrenal adenoma or cancer.