Extraosseous spinal chordoma. Case report.

An extraosseous extradural tumor of the lumbar region with the histological appearance of chordoma produced symptoms in a 58-year-old woman. The tumor occupied the epidural space and produced scalloping of the adjacent vertebral body and pedicle without associated bone destruction. The location of the tumor within Batson's plexus and lack of osseous connection facilitated complete removal. Although the lesion exhibited the classic histological features of a chordoma, it differed significantly in its extraosseous location. Like the rare intradural chordoma arising in the cranium, this tumor presumably represents neoplastic development in an extraosseous notochordal rest.