What is (are) Chordoma ?
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.  Chordomas can occur anywhere along the spine. Approximately half of all chordomas occur at the base of the spine; approximately one third occur at the base of the skull. Chordomas grow slowly, extending gradually into the surrounding bone and soft tissue. The actual symptoms depend on the location of the chordoma. A chordoma at the base of the skull may lead to double vision and headaches. A chordoma that occurs at the base of the spine may cause problems with bladder and bowel function. Chordomas typically occur in adults between the ages of 40 and 70. In many cases, the cause of the chordoma remains unknown. Recent studies have shown that changes in the T gene have been associated with chordoma in a small set of families. In these families an inherited duplication of the T gene is associated with an increased risk of developing chordoma. People with this inherited duplication inherit an increased risk for the condition, not the condition itself.