title: Cystic paraganglioma of the anterior mediastinum.
abstract: Paraganglioma of the mediastinum is an extremely uncommon neoplasm, and the concurrent finding of cystic changes has yet to be reported in the literature. We report a case of a 43-year-old man presenting with chest pain and left arm paresthesias. Imaging studies revealed a well-defined cystic lesion located in the anterior mediastinum, with the patient undergoing subsequent surgical resection of the mass. Grossly, the heterogenous mass measured 6.0 × 3.6 × 1.7 cm, with prominent cystic spaces and scattered solid areas. Microscopic examination revealed pseudocystic spaces with proliferation of large epithelioid cells with abundant eosinophilic cytoplasm, moderate pleomorphic nuclei, and prominent nucleoli, in a nested pattern of growth along the cysts walls. Immunohistochemical stains showed strong positivity for chromogranin, synaptophysin, and CD56 in the epithelioid cells, with negative staining for cytokeratin AE1/AE3, confirming the diagnosis of paraganglioma. S-100 was positive in the intervening sustentacular cells throughout the tumor. Cystic paraganglioma of the anterior mediastinum is a rare neoplasm, which , to our knowledge, has not yet been reported in the English literature, and should be added to the differential diagnosis of cystic lesions of the mediastinum.
authors.affiliation: Department of Pathology and Laboratory Medicine, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
authors.forename: Pablo F
authors.initials: PF
authors.lastname: Ortega
authors.forename: Luis Antonio
authors.initials: LA
authors.lastname: Sosa
authors.forename: Manan
authors.initials: M
authors.lastname: Patel
authors.forename: Eduardo
authors.initials: E
authors.lastname: Zambrano
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism; D019002:CD56 Antigen / Q000378:metabolism; D002864:Chromogranins / Q000378:metabolism; D003560:Cysts / Q000473:pathology* / Q000601:surgery; D015622:Epithelioid Cells / Q000737:chemistry; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008479:Mediastinal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D008482:Mediastinum / Q000473:pathology / Q000601:surgery; D010235:Paraganglioma / Q000000981:diagnostic imaging / Q000473:pathology*; D009418:S100 Proteins / Q000378:metabolism; D016708:Synaptophysin / Q000378:metabolism; D014057:Tomography, X-Ray Computed
chemical_list: D014408:Biomarkers, Tumor; D019002:CD56 Antigen; D002864:Chromogranins; D009418:S100 Proteins; D016708:Synaptophysin