Primary primitive neuroectodermal tumor of the adrenal gland: A unique tumor at an unusual site

Abstract

Ewing sarcoma/Primitive Neuroectodermal Tumor (ES/PNET) is a malignant small round blue cell tumor of neuroectodermal origin that affects bones and soft tissue in children and young adults. ES/PNET is very uncommon in parenchymal organs. We report a case of primary adrenal PNET in a young female having pregnancy induced persistent hypertension. She underwent right adrenalectomy for a large adrenal mass. On histopathology, it was typical malignant round cell tumor (MRCT). Immunohistochemistry confirmed the diagnosis of ES/PNET with expression of CD99, FLI-1 and NKX2.2. Until now, only 38 cases of primary adrenal ES/PNET have been reported in the English literature with just 5 cases from India. Adrenal ES/PNET can be mistaken with other MRCTs like Non-Hodgkin lymphoma and neuroblastoma. Since the biology, treatment and prognosis of these tumors is entirely different, we emphasize that pathologists must be aware of this possibility and try to differentiate them using ancillary techniques.