19 Natural History and Management Options of Skull Base Chordoma

Vinayak Narayan, Fareed Jumah, Bharath Raju, and Anil Nanda

Abstract

Chordomas, constituting 1 to 4% of primary brain tumors, are slow growing extra-axial tumors arising from the ectopic remnants of embryonal notochord cells along the craniospinal axis, presenting with the characteristic features of local invasiveness and clinical malignancy. The clinical characteristics depend on the anatomic location of the tumor. The optimum standard of care for patients with skull base chordoma (SBC) comprises proper clinical and radiological assessment, adequate presurgical planning, ideal surgical approach selection, careful preservation of neurovascular structures, and safe maximal cytoreductive surgical resection. Adjuvant treatment comprises various modalities like proton-beam radiation, photon-based radiation, conventional RT, stereotactic radiosurgery, and charged ion therapy, and most studies report the best results with the proton beam radiation. The overall 5-year survival rate of SBC is around 67% and the overall 10-year survival rate is around 39%. The size of tumor, location, and extent of surgical resection influence long-term local control, overall survival, and recurrence free survival. Older age and greater tumor size were found to be associated with inferior survival.

Schlüsselwörter

skull base - chordoma - natural history - treatment - outcome

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