Unusual presentation of an abdominoinguinal schwannoma.

Schwannoma is a rare, benign peripheral nerve sheath tumor of uncertain origin. This report describes a retroperitoneal cellular schwannoma that extended into the inguinal region. Surgical dissection of a tumor in this site requires an abdominopelvic approach. Histology revealed nodules of pale epithelioid cells separated by fascicles of spindle cells. With immunohistochemistry, no actin was seen. Neurospecific vimentin confirmed the presence of nerve cells. The tumor was completely removed, and as of 6 months later there had been no recurrence. Schwannoma are extremely difficult or even impossible to diagnose preoperatively. If clinicians are faced with an inguinal swelling or herniation and a coexisting abdominal mass, they should perhaps consider radiologic studies that better identify the origin.