Clival Chordoma

OVERVIEW:

Chordomas are locally invasive tumors that arise from the remnant of the primitive notochord. They occur most commonly in the skull base (clivus) and lower spine; approximately 40% of chordomas and chondrosarcomas arise in the clivus. Chordomas are often considered a benign tumor because of their slow growth. However, some chordomas behave aggressively and have more malignant characteristics with extensive invasiveness including a small subset of patients (~10%) that develop metastases to distant sites beyond their site of origin.

SYMPTOMS:

Most patients with a clival chordoma develop headaches and double vision. Less common symptoms include visual loss, hearing loss, difficulty swallowing, facial numbness, in-coordination and motor weakness.

DIAGNOSIS:

These skull base tumors are best diagnosed by MRI and CT scans which will clearly show the extent of tumor and bony destruction. Focused MRIs of the pituitary region, sinuses, temporal bones or internal auditory canals may be indicated to obtain better anatomical detail of a chordoma. Other tests may also be needed prior to surgery such as angiography (typically now performed as a CT angiogram or an MR angiogram), visual field tests, an audiogram or hormonal tests.

TREATMENT:

Initial treatment for a clival chordoma is with surgical removal or debulking. As shown by our recent experience, most clival chordomas and chondrosarcomas can be approached by an endonasal transsphenoidal route with excellent results. However, some extensive and/or laterally placed chordomas may require different skull base surgical approaches. Because chordomas typically invade the bone and dura of the skull base, complete surgical resection is often not possible and continued growth of residual tumor is common. Extensive surgery can certainly improve long term survival but over aggressive tumor removal can be associated with significant complications, most notable of which are increased neurological problems. Most recurrent or residual chordomas are treated with stereotactic radiotherapy (SRT), stereotactic radiosurgery (SRS) or proton beam radiation. Chemotherapy is generally ineffective for treating chordomas although clinical trials of some experimental chemotherapies are available.