Combined diagnostic imaging for retroperitoneal schwannoma

Retroperitonenl tumors are occasionally encountered by gynecologists, and d ifferential diagnosis from adnexal tumors is important, however, it is diff icult in many cases. We report a case in which we preoperatively diagnosed a benign solid tumor in the retroperitoneum of the pelvic cavity on the bas is of a variety of diagnostic images, including FDG-PET. Postoperative hist ological examination showed a benign schwannoma in the pelvis. We discuss t he usefulness of FDG-PET combined with MRI and other diagnostic images as a means of differentiating between the characteristics of retroperitoneal tu mors.