A chondrosarcoma is a malignant bone tumor. Chondrosarcomas arise from the cartilage-producing cells around bones.
Neurosurgeons at the Spine Hospital at the Neurological Institute of New York specialize in chondrosarcomas of the spine, which represent about 5%-10% of chondrosarcomas. Chondrosarcomas can occur in the bones of the lower back (lumbar spine), the middle and upper back (thoracic spine), the neck (cervical spine), or the top of the spine, near the base of the skull.
There are several types of chondrosarcoma. Tumor types that occur most commonly in the spine include:
- De-differentiated chondrosarcomas: aggressive tumors that have two distinct components, one inside and one outside of cartilage. Most common in middle-aged adults.
- Mesenchymal chondrosarcomas: extremely rare, often aggressive tumors that usually affect young adults
Individual tumors of all types also receive ‘histological grades’ based on the appearance and behavior of their cells under a microscope. Grade I tumors are slow-growing and their cells are only slightly abnormal. Grade III tumors grow more quickly, their cells are more abnormal, and they are more likely to spread. Grade II tumors are intermediate between I and III. Chondrosarcomas of the spine may be of any grade.
Chondrosarcomas of the spine usually cause bone pain that is not relieved by rest.
Chondrosarcomas of the skull base may affect nearby cranial nerves and the brainstem. Symptoms may include headaches, dizziness, double vision, other vision changes, hearing loss, weakness, or hormonal dysfunction.
Causes and Risk Factors
The exact cause of chondrosarcoma is not known. It is most common in the 4th and 5th decades of life, and is slightly more common in men than women.
Tests and Diagnosis
Computed tomography (CT) scans are used to examine the bones of the spine. Magnetic resonance (MR) scans may also be used to distinguish the tumor from other sensitive structures in the area. A “contrast agent” may be injected before a CT or MRI so that neurosurgeons can better visualize the tumor against the normal structures in the background.
Plain X-rays are not typically useful in visualizing chondrosarcomas.
Spinal angiography, which reveals blood flow in the area around the tumor, may also be used. This imaging study can help direct the surgical approach to the tumor by showing which blood vessels are affected by the tumor.
The goal of chondrosarcoma surgery is complete tumor removal. However, the location of these tumors and their involvement with important structures may make complete removal difficult or impossible.
The neurosurgeons at The Spine Hospital at The Neurological Institute tailor a surgical plan to each individual patient. Complete removal, when possible, may involve combined or multiple surgical procedures or approaches. Depending on the tumor location, surgical options include:
- anterior cervical corpectomy
- cervical laminectomy
- lumbar laminectomy
- microsurgical tumor removal
- stereotactic radiosurgery
- thoracic corpectomy
- thoracic laminectomy
Spinal fusion and stabilization with metallic implants is often performed following complete tumor removal.
Stereotactic radiosurgery, which uses a highly focused beam of radiation to target the cancer cells, may be used along with surgery. However, chondrosarcomas are notoriously resistant to chemotherapy and radiation therapy.