Chordoma is part of a group of malignant bone and soft tissue tumors called sarcomas. Chordomas account for about 3 percent of all bone tumors and about 20 percent of primary spinal tumors. They are the most common tumor of the sacrum and cervical spine. A chordoma tumor usually grows slowly, often without symptoms at first, and then might cause symptoms for years before doctors find it.

Chordomas are complicated tumors to treat due to the involvement of critical structures such as the brainstem, spinal cord, and important nerves and arteries. They can also come back, or recur, after treatment — usually in the same place as the first tumor. This is called a local recurrence. In about 30 to 40 percent of patients, the tumor eventually spreads, or metastasizes, to other parts of the body.

There are no known environmental, dietary, or lifestyle risk factors for chordoma. The vast majority of chordomas occur at random and not as a direct result of an inherited genetic trait; however, there are several genetic factors associated with chordoma. For example, more than 95 percent of individuals with chordoma have a single-letter variation, called a SNP (“snip”), in the DNA sequence of a gene called brachyury (also known as TBXT). This SNP causes an increase in the risk of developing chordoma, but does not by itself cause chordoma. In fact, a large portion of the general population has this SNP, but individuals who have the SNP are still very unlikely to develop chordoma – the chances are less than two in a million. To learn more about the SNP and what it means for chordoma patients and family members, clickhere.

Familial chordoma
There are a handful of known cases where multiple members of the same family are affected by chordoma. This indicates that in these very rare instances, a strong genetic predisposition for chordoma can be inherited. It is known that some of the families with familial chordoma have an extra copy of the brachyury gene, but currently, there is no available test for the presence of extra copies of the gene. The National Cancer Institute is currently conducting a genetics study to identify additional hereditary causes of chordoma. Clickhere for details on participating in this study.

Tuberous Sclerosis Complex
Chordomas have been reported at a higher incidence in children with the genetic disease Tuberous Sclerosis Complex (TSC). Changes in either of two genes involved in Tuberous Sclerosis Complex (TSC1 and TSC2) can cause a predisposition to developing chordoma.