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Two-Stage En Bloc Resection of Multilevel Cervical Chordomas With Vertebral Artery Preservation: Operative Technique.

BACKGROUND
En bloc excision of cervical chordoma is a technically complex procedure, due to the involvement and closeness of the tumor to the spinal cord, cervical nerve roots, and vertebral arteries. Studies have previously shown that en bloc excision of chordomas with negative margins improves local control and prolongs disease-free survival compared with intralesional excision. True en bloc spondylectomy in the cervical spine is not feasible since bilateral vertebral artery sacrifice is not possible. However, for lateralized tumors, en bloc excision of chordoma can be performed with unilateral vertebral artery preservation by parasagittal osteotomy.


OBJECTIVE
To describe the operative technique of performing en bloc excision of cervical chordoma via parasagittal osteotomy.


METHODS
Four patients underwent en bloc excision of multilevel cervical chordomas via parasagittal osteotomy between 2008 and 2016. These 4 cases of chordoma were at the upper-cervical, mid-cervical, and cervicothoracic regions. We analyzed the tumor location, oncological staging, surgical technique, and perioperative complications.


RESULTS
All 4 patients underwent en bloc excision of chordoma with expandable cage reconstruction and posterior instrumentation. Cervical nerve roots were sacrificed in 2 patients, and vertebral artery ligation was performed in 3 patients. Complications include new neurologic deficit, implant failure, and pharyngeal erosion after radiation. No tumor recurrence was seen.


CONCLUSION
Parasagittal osteotomy is a useful alternative to en bloc spondylectomy in the treatment of lateralized multilevel cervical chordoma, preserving one vertebral artery while still achieving an en bloc resection.