Chordoma

Large expansile infiltrative lesion in the S1 and S2 vertebral bodies with pre and paravertebral and epidural components with consequent neural compromise and spinal canal narrowing.
Chordomas are rare tumors that arise from embryonic notochordal remnants along the length of the neuraxis at developmentally active sites.Chordomas are rare neoplasms. As primary intracranial neoplasms, they only constitute 0.2% of all CNS tumors. Chordomas generally occur in 3 locations, which are, in descending order of frequency, the sacrum, intracranially at the clivus, and along the spinal axis.CT scan or MRI studies are indicated to evaluate the extent of the tumor and to identify the tissues that the chordoma has infiltrated.The 5-year survival rate is estimated to be 51%, and the 10-year survival is estimated to be 35%. Factors that may improve prognosis are young age, complete resection, and the addition of radiation therapy in incompletely resected tumors.

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