Type of disease: Rare conditions
A chordoma is a rare tumor that develops from cells of the notochord, a structure that is present in the developing embryo and is important for the development of the spine. The notochord usually disappears before birth, though a few cells may remain embedded in the bones of the spine or at the base of the skull. A chordoma occurs when these notochord cells start to grow into a tumor and spread into surrounding bone. Approximately one third of chordomas occur at the base of the skull in a bone called the clivus and the most common symptoms are double vision (diplopia) and headaches. The average age of diagnosis for chordomas of the skull base is 38 years. Treatment often begins with surgery to remove as much of the tumor as possible, and radiation therapy may follow surgery to destroy any remaining tumor cells. Chordomas often grow back in the original location after treatment (known as a recurrence); they do not often spread to distant parts of the body (metastasize). Though the cause of chordomas is unknown, there is currently a study aimed at identifying a potential genetic predisposition to this disease; more information on this study can be found on the National Cancer Institute’s web site.Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.