UNUSUAL DIAGNOSIS OF A MEDIASTINAL MASS

Abstract

TOPIC: Lung Pathology TYPE: Medical Student/Resident Case Reports INTRODUCTION: Paragangliomas are rare neoplasms with an annual incidence of 0.8 per 100,000-person years [1]. Mediastinal paragangliomas represent only 2% of paragangliomas [2]. However, with increased availability of imaging, the number of these neoplasms found incidentally in asymptomatic individuals is increasing. This case report presents an asymptomatic paraganglioma in the mediastinum. CASE PRESENTATION: 51-year-old white female with a history of hypertension and anxiety who presented with worsening shortness of breath, weakness, fever, chills and nonproductive cough. The patient was admitted because she failed outpatient treatment with amoxicillin/clavulanate. CT chest revealed basilar consolidation and a bulky centrally necrotic subcarinal nodal mass. She was discharged 5 days later after one dose of dexamethasone as well as a course of IV azithromycin and ceftriaxone. Repeat CT chest 6 weeks later showed a persistent enhancing soft tissue mass in the mediastinum measuring 4.8 x 2.9 cm. Pulmonology was consulted and performed an endoscopic bronchial ultrasound biopsy with fine-needle aspiration that revealed mediastinal lymphadenopathy as well as a partial narrowing from mass effect in the left main bronchus, left lower lobe and the lingula. Histologic sections and immunohistochemistry confirmed the diagnosis of paraganglioma. The patient was sent to thoracic surgery to consider resection and is currently awaiting workup with endocrinology. DISCUSSION: Mediastinal paraganglioma is a rare tumor and often because of their location biopsy to confirm diagnosis is often delayed. Half of patient's are asymptomatic [3] and may only be diagnosed incidentally or once mass effect produces clinical symptoms to initiate workup. Clinical symptoms in symptomatic patients are often from catecholamine hypersecretion causing palpitations, sweating, headaches and most commonly hypertension. Non-catecholamine symptoms may include hoarseness, shortness of breath or dysphagia depending on the location of the tumor. Surgical tumor removal remains the cornerstone of treatment. However, resection may not be feasible due to these tumors being highly vascular and neighboring critical vascular structures. CONCLUSIONS: Paraganglioma is a rare tumor in the mediastinum that is usually asymptomatic and found incidentally. Surgical resection can be curative. REFERENCE #1: Beard CM, Sheps SG, Kurland LT, Carney JA, Lie JT. Occurrence of pheochromocytoma in Rochester, Minnesota, 1950 through 1979. Mayo Clin Proc. 1983 Dec;58(12):802-4. PMID: 6645626. REFERENCE #2: Ghayee HK, Havekes B, Corssmit EP, et al. Mediastinal paragangliomas: association with mutations in the succinate dehydrogenase genes and aggressive behavior. Endocr Relat Cancer 2009; 16:291. REFERENCE #3: Sutton MG, Sheps SG, Lie JT. Prevalence of clinically unsuspected pheochromocytoma. Review of a 50-year autopsy series. Mayo Clin Proc. 1981 Jun;56(6):354-60. PMID: 6453259. DISCLOSURES: No relevant relationships by Haytham Adada, source=Web Response No relevant relationships by Mahmoud Amarna, source=Web Response No relevant relationships by Camelia Chirculescu, source=Web Response No relevant relationships by Trevor Elswick, source=Web Response