Chordoma and Chondrosarcoma (Skull Base)
Chordoma and chondrosarcoma are rare, locally aggressive malignant tumors arising from the skull base bones. Chordoma develops from embryonic notochord remnants and chondrosarcoma from cartilage tissue; they are considered together because of their similar location and treatment.
最終更新: 2026-06-07
Definition
Chordoma and chondrosarcoma are primary malignant tumors of the skull base bones. They are addressed together because their clinical presentation, location and treatment are similar. Both are rare. Chordoma arises from remnants of the embryonic notochord (the precursor of the axial bone of the spine and skull base) and is often located in the midline at the clivus. Chondrosarcoma arises from the cartilage cells of bone and tends to lie more laterally (the petroclival region).
Clinical Behavior
Both tumors usually grow slowly but behave locally aggressively, destroying surrounding bone and invading the cavernous sinus, brainstem, clivus and adjacent structures. Chordoma has a high tendency for local recurrence; distant metastasis is less common. Chondrosarcoma, especially the low-grade (grade 1-2) type, generally follows a less aggressive course and has a better prognosis than chordoma. The definitive distinction is made by histopathological and immunohistochemical examination.
Symptoms
The most common symptoms come from cranial nerve compression. The most frequently affected nerve is the sixth (abducens) nerve, causing double vision. Trigeminal nerve involvement causes facial pain and numbness, facial nerve involvement causes facial asymmetry, and involvement of the hearing-balance nerve causes hearing loss and dizziness. Lower cranial nerve involvement leads to swallowing and voice disturbances. Occipital headache and nasal obstruction may also occur. Because of slow growth, diagnosis is often delayed.
Diagnosis
Contrast-enhanced brain MRI together with skull base CT is the gold standard for diagnosis. On MRI, chordoma is typically midline and markedly hyperintense on T2 sequences; CT shows bone destruction in detail. Histopathological and immunohistochemical examination of a biopsy/surgical specimen is required for the definitive diagnosis and to distinguish the two tumors; the brachyury marker is characteristic of chordoma. Imaging defines the tumor's relationship to critical neurovascular structures.
Treatment
The core treatment principle is maximal safe surgical resection followed by adjuvant high-dose radiation (usually proton) therapy. Because the tumor encases critical structures, complete removal is often not possible; subtotal resection followed by radiotherapy is therefore the standard approach. Surgery uses the endoscopic endonasal approach for midline tumors and lateral skull base approaches for more laterally placed lesions. As these tumors resist standard radiotherapy, proton/particle therapy is prominent.
Prognosis and Follow-up
Prognosis depends on the tumor type and grade, the extent of resection and the location; chondrosarcoma (especially low-grade) generally has a better prognosis than chordoma. Local recurrence is a major concern, so long-term regular MRI follow-up is required. Cranial nerve impairments may partly improve after surgery or may be permanent. Outcomes differ by patient and cannot be guaranteed.
参考文献
- Greenberg MS. Greenberg's Handbook of Neurosurgery. 10th ed. Thieme; 2023:825.
- Winn HR, ed. Youmans Neurological Surgery. 6th ed. Saunders; 2011:1587.
- Stacchiotti S, et al. Building a global consensus approach to chordoma. Lancet Oncol. 2015.
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