MON-LB040 Challenge in Diagnosing and Treating of Mediastinal Paraganglioma

Abstract

Paraganglioma is a rare type of neuroendocrine tumor of the autonomicnervous system.1 It is extremely rarely present in mediastinum (less than2%).2Case report We report a 43 years-old woman, she was referred to our clinic with ahistory of high blood pressure (BP) for two years, accompanied by spellsof sweating, headache, anxiety and palpitation. She was provisionaldiagnosed with essential hypertension and was on four medications onmaximum dose.The patient declined any previous surgical history, and review of systemswas unremarkable. On examination, she was conscious and alert. Her vitalsigns were within normal limit. She reported to our clinic with homereadings of BP ranging from 150-180 mmHg systolic and 90-100 mmHgdiastolic.Initial investigations of basic chemistry, renal profile, hormonal profile,aldosterone, and renin were within the normal range.Serum Normetanephrine was 800 ng/L (normal < 180 ng/L), 24 hoursurine of Normetanephrine was 5205 microgram/24 hours (normal < 600microgram/24 hours), and 24 hours urine Metanephrine was withinnormal. CT scan of the adrenal and MRI abdomen showed normal adrenalglands and no mass in the abdomen. MIBG scan was normal for the wholebody. An unusual location of the Paraganglioma was suspected, andfurther images were carried on. A CT chest showed 4x4 cm posteriormediastinal mass in area of Aortopulmonary window, adherent toposterior wall of Aorta and pulmonary artery. Positron EmissionTomography (PET) scan was done prior to the surgery.Surgical resection of the mass with reconstruction of both pulmonaryartery and pericardium was done without any complications. Moreover,histopathology confirmed the diagnosis of Paraganglioma.The patient was followed up with a CT scan six months post-operativelyas an outpatient, along with 24-hour urine Metanephrine and Normetanephrine. All labs and imaging were normal. The patient hadanother Normetanephrine measurement twelve months later and it wasnormal. Now, she has been followed for seven years with no moresymptoms and normal BP readings. All of her antihypertensive agentswere discontinued. ConclusionWe experience an unusual location of Paraganglioma at the mediastinum,which is representing less than 2% of all Paraganglioma. However, in thepresence of characteristic of Paraganglioma symptoms, a thoroughassessment should be carried out and such location of mediastinumshould be suspected and investigated.