Chordoma is a rare slow-growing neoplasm thought to arise from cellular remnants of the notochord. The evidence for this is the location of the tumors (along the neuraxis), the similar immunohistochemical staining patterns, and the demonstration that notochordal cells are preferentially left behind in the clivus and sacrococcygeal regions when the remainder of the notochord regresses during fetal life. [Source: Wikipedia ]

OrphaNet reference
May Cause
Blow-out bone lesion
Cerebellopontine angle lesion
Densely sclerotic vertebra
Destructive lesion in petrous apex
Enhancing mass in cerebellopontine angle cistern
Enhancing sellar lesion
Enhancing suprasellar lesion
Enlarged intervertebral foramen
Enlarged superior orbital fissure
Enlargement or erosion of sella turcica
Erosion of sphenoid wing
Erosion of the petrous ridge, pyramid, or apex
Extradural lesion with abnormal adjacent bone
Extradural spinal lesion
Facial nerve lesion outside the temporal bone
Focal vertebral sclerosis
Focally dense skull base
Hyperdense sellar lesion
Hyperdense suprasellar lesion
Increased prevertebral space in an adult
Intracranial lesion involving the orbit
Isodense intracranial lesion
Jugular foramen lesion
Large destructive bone lesion
Large pelvic soft-tissue mass
Lytic vertebral lesion
Malignant primary bone neoplasm
Middle cranial fossa lesion
Moderately enhancing intracranial lesion
Nasopharyngeal extension of intracranial neoplasm
Paranasal sinus mass
Parasellar calcification
Parasellar lesion
Paraspinal soft-tissue mass
Posterior fossa lesion
Posterior skull base lesion
Presacral mass
Sacral neoplasm
Sacrococcygeal lesion
Sacrococcygeal mass
Sacroiliac joint disease
Sellar lesion
Sinonasal lesion
Skull base lesion
Solitary collapsed vertebra
Solitary intracranial calcification
Solitary poorly demarcated osteolytic bone lesion
Spinal block
T1-hypointense intracranial lesion
T1-isointense intracranial lesion
T2-hyperintense intracranial lesion
Tumor crossing an intervertebral disk
Tumor-like bone destruction with little periosteal reaction
Vertebral neoplasm