PSUN15 Recurrence of Benign Pheochromocytoma

INTRODUCTION: Pheochromocytoma is a rare, usually benign, tumor of adrenal medulla. The prevalence is about 4.5-6.5%. The common presenting symptoms are headache, palpitations, diaphoresis, flushing, hypertension, and tachycardia. The high catecholamine levels can also result in arrhythmias, cardiomyopathy, stroke, and even death. It can also be asymptomatic and diagnosed as an adrenal incidentaloma on routine imaging. Due to its diverse and non-specific presentation, it is often called a great mimic in medicine. It is diagnosed both biochemically with plasma or urine metanephrines and by imaging (CT or MRI). The first line treatment is surgical resection of adrenal gland, adrenalectomy. Resected tumors should be pathologically confirmed for absence of malignancy. The recurrence of benign pheochromocytoma after adrenalectomy is rare. Recurrence rate following adrenalectomy is 6.5-16.5%. There are no identified predictors of recurrence but usually it occurs after 2-3 years. Annual imaging and biochemical testing for plasma and urinary metanephrines is recommended for early diagnosis of recurrence. CASE PRESENTATION: A middle aged female with past medical history of uncontrolled hypertension and uncontrolled diabetes mellitus underwent CT scan for abdominal pain, fatigue, and unintentional weight loss. She also complained of intermittent palpitations, chest heaviness, sweating, facial flushing, and headaches. Family history was negative for endocrinopathies or endocrine malignancies. CT showed 12 cm right adrenal mass. Plasma metanephrines were ordered given the imaging findings and they were elevated at more than 13000 pg/nl (normal < 60 pg/ml). All other adrenal hormones were within normal range. She was diagnosed with pheochromocytoma and underwent right adrenalectomy. The tumor was confirmed to be benign by histopathology. Post-surgery her symptoms resolved, and biochemical tests normalized with plasma metanephrine at 35 pg/ml. She presented again 4 years later with similar symptoms. Patient experienced palpitation and noted to have high blood pressure at home. She had also been experiencing flushing and having a sense of impending doom. On examination the patient was diaphoretic and review of systems was positive for heat intolerance, polydipsia and polyuria. EKG revealed sinus tachycardia and blood glucose was elevated. Labs revealed elevated plasma metanephrine and normetanephrine levels. Renin activity and plasma aldosterone levels were normal. CT sc