Multifocal presentation of gangliocytic paraganglioma in the mediastinum and esophagus.
Gangliocytic paraganglioma (GP) is a rare, typically benign tumor that shows neuroectodermal (neurosustentacular or Schwannian and neuronal) and neuroendocrine differentiation. Once thought to arise exclusively in the periampullary region as a solitary lesion, recent reports have documented both origin of GP in a variety of extra-duodenal sites as well as synchronous multifocal presentation of the tumor. Herein, we describe the first reported case of simultaneous occurrence of GP in the superior mediastinum and esophagus. A mass in the mid-distal esophagus and a separate mass in the superior mediastinum at the thoracic inlet were found in a 58-year-old woman by computed tomography scan. Subsequent biopsy of the superior mediastinal mass showed nests of epithelioid tumor cells coexisting with ganglioneuromatous elements, whereas biopsy of the esophageal mass showed nests of epithelioid cells with interspersed ganglion cells. The epithelioid tumor cells showed diffuse immunohistochemical expression of keratin (CAM 5.2), chromogranin, and synaptophysin supporting true neuroendocrine differentiation; ganglion cells expressed S-100 protein and neurofilament protein; and the spindled elements expressed S-100 protein, neurofilament protein, and glial fibrillary acidic protein indicating Schwannian differentiation. The finding of another GP occurring outside the periampullary region bolsters the argument for a stem cell origin of this unusual tumor.