Endocrine Abstracts

JOINT58

Introduction.: The usual location of oncocytic cell tumors is in kidney, salivary gland, thyroid gland, parathyroid, and pituitary gland, although they have also been reported in other locations. Adrenal oncocytomas (AO) are extremely rare, mostly benign and non-functional, however they can be hormonally overproduced and potentially malignant. We present a case of resistant hypertension resulting from aldosterone-producing AO.

Case presentation: A 63-year-old male hospitalized in the emergency department for hypertensive encephalopathy, with high blood pressure levels resistant to medication. The patient was known to be hypertensive for 15 years with current antihypertensive therapy of Olmesartan plus 40/12.5 mg daily, Lercanicipine 20 mg daily and Moxonidine 1 mg daily. Routine laboratory examinations showed K+ 3.2 mmol/l and other laboratory parameters within the norm. Echocardiography showed severe concentric hypertrophy of the left ventricle with other echographic indices within the norm. According to the criteria of the European Society of Endocrinology for the exploration of secondary hypertension (Resistant HTN with unexplained hypokalemia and severe concentric hypertrophy of the left ventricle) plasma renin activity, aldosterone and their ratio were measured, which resulted in compatibility for primary hyperaldosteronism. Adrenal CT identified a solid mass in the left adrenal gland which was 15×10 mm in size, consistent with adenoma. The patient underwent surgical intervention of the adrenal mass, which was followed by stabilization of blood pressure values. The histopathologic study showed cortical adenomas with oncocytic cells.

Discussion: About 1.8% of adrenal tumors are oncocytic tumors, which are discovered incidentally and present as benign, nonfunctioning tumors. According to recent data, about 20% of adrenal oncocytomas are malignant and 30% of them are functional, causing symptoms related to hormonal overproduction. Histological diagnosis differentiates these tumors from adrenal adenomas.