Table of Contents
Diagnostic and Therapeutic Endoscopy
Volume 2011, Article ID 198029, 3 pages
Case Report

EUS-FNA for the Diagnosis of Retroperitoneal Primitive Neuroectodermal Tumor

1Division of Gastroenterology, Department of Internal Medicine, University of Toledo Medical Center, 3000 Arlington Avenue, Toledo, OH 43614, USA
2Division of Gastroenterology, Department of Internal Medicine, Henry Ford Health System, Henry Ford Hospital, Detroit, MI 48202, USA

Received 30 August 2010; Accepted 12 February 2011

Academic Editor: Kazuo Inui

Copyright © 2011 Aijaz A. Sofi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Primitive neuroectodermal tumor (PNET) is a rare “small round blue cell tumor” that is diagnosed by open biopsy or percutaneous biopsy of the lesion under radiologic guidance. In this case report, we present a novel approach to the diagnosis of a retroperitoneal PNET by endoscopic ultrasound- (EUS-) guided fine needle aspiration (FNA). A 35-year-old man presented with the history of left-sided flank pain and swelling of 3-weeks duration. Computerized tomography (CT) scan of his abdomen revealed a 12.8 × 13 × 12.5 cm cystic and solid mass arising from the retroperitoneum and displacing the third and fourth portions of the duodenum. He underwent EUS which revealed a well-circumscribed heterogeneous mass abutting the inferior portion of the stomach. EUS-FNA of the mass revealed malignant cells consistent with primitive neuroectodermal tumor (PNET)/Ewing's sarcoma. EUS-guided FNA is an appropriate technique for diagnosing retroperitoneal PNET/Ewing's sarcoma.