MON-383 Sporadic Bilateral Pheochromocytoma with Renal Pelvis Paraganglioma: A Rare Coexisting Occurrence

Abstract

Pheochromocytomas (PHEO) and paragangliomas (PGL) are rare neuroendocrine catecholamine-secreting tumors that arise from chromaffin cells of the adrenal medulla and the extra-adrenal autonomic paraglanglia respectively. The natural course of this disease increases morbidity and mortality. Most cases are sporadic, unicentric and unilateral and occur in the 4th and 5th decade of life. Hereditary disease typically presents at a younger age and are likely to be bilateral and linked to germline genetic mutations. This is the case of a 26 year-old lady with history of early onset high blood pressure (HTN) in the setting of bilateral (B/L) adrenal masses. At 21 years old, she was diagnosed with HTN accompanied with symptoms of depression, cry spells, anxiety, tachycardia and episodes of chest pain that warranted frequent ER visits. She was started on labetalol, lisinopril and hydrochlorothiazide. The work-up for early onset HTN prompted urine fractionated catecholamine collection that revealed normal metanephrines but elevated normetanephrines more than 10 times above the upper limit of normal. SPECT CT abdomen and pelvis showed a 3 cm left adrenal mass lesion compatible with a pheochromocytoma and a 4.5cm complex but dominantly low right adrenal mass with no significant uptake suggestive of a benign adenoma. Dexamethasone suppression test, 24-hour urine free cortisol, aldosterone, plasma renin activity, calcitonin, calcium and PTH levels were within normal limits. Repeated testing showed urine norepinephrine 793 mcg/24h (normal 15-100), urine dopamine 641mcg/24h (normal 52-480), normal urine epinephrine, plasma normetanephrines 2383pg/ml (normal <148) and normal plasma metanephrines. With the diagnosis of Normetanephrine secreting PHEO, She was alpha blocked to undergo left adrenalectomy. Final pathology confirmed left PHEO. After surgery lisinopril was restarted due to HTN, and cathecholamines mildly improved but remained elevated. 7 month later CT abdomen w/wo contrast plus PET CT described status post left adrenalectomy; interval decrease in size of the right adrenal mass now avidly positive reflecting an additional PHEO and an enhancing mass in the left renal pelvis and left renal calyx consistent with a PGL, retrospectively also present in prior imaging. Interestingly no germline mutation was identified in genetic analysis. Simultaneous PGL and PHEO is rare with an incidence of 0.3 and 1 per 100000. Our detailed literature review found only two cases with bilateral PHEO and PGL. Less than 17 cases with renal PGL have been published. Our case is the first sporadic B/L PHEO with renal PGL ever reported. Although no specific genetic mutation was found in our patient, we propose close monitoring with imaging and to be continued in patients with a hereditary pattern. As genetic technology continues to evolve we will be able to identify a clear mutation in this type of patients.