MRI features are likely representing clival chordoma, which was proven on histopathology postoperatively. 

Clival chordoma represent the second commonest site of chordoma (sacrococcygeal location being the first location). Chordomas are uncommon malignant tumors that account for 1% of intracranial tumors and 4% of all primary bone tumors. 

They originate from embryonic remnants of the primitive notochord (earliest fetal axial skeleton, extending from the Rathke's pouch to the coccyx). Since chordomas arise in bone, they are usually extradural and result in local bone destruction. They are locally aggressive, but uncommonly metastasize.