Retroperitoneal neurilemoma diagnosed by endosonographically guided fine needle aspiration

Retroperitoneal neurilemoma is an often asymptomatic benign tumor that is usually discovered incidentally. We report a case of retroperitoneal neurilemoma diagnosed via endosonographically guided fine needle aspiration and emphasize the importance of obtaining a definite diagnosis before surgical treatment. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:241–243, 2006