Resident Atrium Health Carolinas Medical Center Charlotte, North Carolina, United States
Introduction : Pheochromocytomas and paragangliomas are rare neuroendocrine tumors(NETs) with an incidence estimated at 2-8 cases per 1 million annually. They are functional catecholamine-producing tumors that arise from sympathetic adrenomedullary chromaffin tissue. In extremely rare cases they are associated with ectopic production of ACTH. This can lead to mixed presentations with diagnostic and treatment challenges.
Case(s) Description : A 51-year-old female with history of hypertension was sent to the emergency room for hypokalemia of 2.3 mmol/L (normal 3.5-5.1) and elevated blood pressures (BP).She endorsed severe headaches, facial flushing, and proximal muscle weakness. Labs showed elevated plasmametanephrines of 281.7pg/mL (normal 0-88) and normetanephrines > 10000pg/mL (normal 0-244). Abdominal imaging revealed a9.4 cm left retroperitoneal mass concerning for pheochromocytoma and multiple hepatic lesions. Patient was admitted to the intensive care unitfor hypertensive emergencyand altered mental status. Brain magnetic resonance imaging was normal. Biopsy of a liver lesion showed metastatic pheochromocytoma. Endocrinology was consulted and started alpha blockade.Coursewas complicated by ongoing uncontrolled BP, hyperglycemia, and refractory hypokalemia. Further work-up revealed an elevated random serum cortisol level and an ACTH of 374pg/mL (normal 7.2-63.3). Low-dose dexamethasone suppression test showed a high cortisol of 82.3 ug/dL (normal < 1.8) concerning for Cushing’s syndrome from adrenal tumor ACTH co-secretion.Ketoconazole was later added for treatment. Patientwaspresented attumor board anddecisionwas made to pursue debulking surgery for symptomatic control.She underwent open left adrenalectomy, nephrectomy, distal pancreatectomy,and partial hepatectomy. She toleratedsurgery,howevercoursewascomplicated by progressive multisystem organ failure leading to a transition to comfort-directed care.
Discussion : Cushing’s syndrome, especially from ectopic ACTH production, has a poor prognosis and increased mortality. The inpatient team focused on treating the patient’s pheochromocytoma and hypertension, however refractory hypokalemia was a clue that something other than catecholamine production was going on. In retrospect, we would consider earlier and more aggressive medical therapy for her Cushing’s, or even bilateral adrenalectomy to stop the cortisol response to ectopic ACTH given she was already undergoing an aggressive surgical procedure. This case highlights the importance of recognizing that NETscan produce ectopic hormones like ACTH. Early clinical suspicion secondary to refractory symptoms and hypokalemia should prompt earlier diagnosis and management.
