Management of Incidental High-grade Dedifferentiated Chondrosarcoma by Triple Vertebrectomy and Anterior Reconstruction Using a Posterior-only Approach

Abstract

Introduction: Chondrosarcomas of the spine most commonly present with pain and neurological involvement and surgical resection is the standard of care. However, the involvement of 3 contiguous vertebral bodies is rare and surgical en bloc resection may not be possible in all cases, particularly when there is an extra compartmental spread. Materials and Methods: We report a case of incidentally detected biopsy-proven chondrosarcoma who was treated by a triple vertebrectomy through a posterior-only approach. Results: Three nerve roots had to be sacrificed on one side and 1 nerve root on the other side. The radicular arteries were freed from the vertebral body and tumor mass. Since the pedicles and lamina were involved and there was an extra compartmental spread to the nearby vital structures, an en bloc resection could not be accomplished. Anterior reconstruction was performed through the posterior approach using a MESH cage. Posterior stabilization using pedicle screws and rods was done 3 levels above and below the vertebrectomy levels. Biopsy suggested a very rare aggressive variant of spinal chondrosarcoma labeled as a dedifferentiated chondrosarcoma. Postoperative Image-guided radiotherapy was given and the patient was doing well at 1-year follow-up. Discussion: Primary chondrosarcoma involving 3 or more vertebra has been rarely reported in the literature and no specific guidelines exist on the management of such tumors. The aim of this case report was to emphasize the feasibility of doing a triple vertebrectomy and anterior reconstruction using a posterior-only approach. Posterior-only approach allows for complete tumor removal and circumferential stabilization in a single setting.