Primary Ewing's sarcoma/peripheral primitive neuroectodermal tumor at the vertex of the skull with elevated serum carcinoembryonic antigen: Case report

A primary Ewing's sarcoma arising in the skull is relatively rare. Although a small number of case reports noted elevated carcinoembryonic antigen (CE A) in patients with primary central nervous system (CNS) neoplasms, there i s no report of Ewing's sarcoma/peripheral primitive neuroectodermal tumor ( PNET) with elevated serum levels of CEA. A 7-year-old boy who had episodes of headache and vomiting had noticed a solid mass in the vertex of the head . Imaging studies revealed a large intra- and extracranial tumor at the ver tex of the skull. Hematological examination demonstrated high serum levels of CEA: 91.09 ng/ml. The patient initially underwent an embolization of the bilateral middle meningeal arteries with Gelfoam particles. One week later , the patient was operated on and a subtotal resection of the tumor was per formed. On histopathological and molecular genetic examination, the tumor w as diagnosed as a Ewing's sarcoma/peripheral PNET. Immunohistochemical stud y showed strongly positive staining for CEA in the tumor cells. The serum l evel of CEA was normalized at 0.83 ng/ml after the tumor was removed and th e boy underwent radiotherapy and 3 courses of chemotherapy. This is the fir st reported case of a primary Ewing's sarcoma/peripheral PNET at the vertex of the skull with elevated serum CEA.