Chordoma Health Article

Definition

Chordomas are rare tumors of the central nervous system (brain and spinal cord).

Description

Chordomas are slow-growing tumors that invade bone and tissue surrounding the spinal column. They rarely spread to other parts of the body, but they can cause considerable damage or death because they destroy bone and soft tissue and often grow along the roots of nerves, putting pressure on the nerves and disrupting their function.

Chordomas appear at the base of the skull about 60% of the time and in the sacrum, located at the base of the spine, about 30% of the time. The other 10% of chordomas can occur anywhere else along the spinal column.

Demographics

Chordomas are very rare, accounting for between 1-4% of tumors of the brain and spinal column. Chordomas that occur at the base of the skull are most common in adults between 30 and 40 years of age. Those tumors that arise at the sacrum, located at the base of the spine, most commonly appear in older adults between the ages of 50 and 70. Chordomas are about twice as common in men as they are in women.

Causes and symptoms

During the fourth through sixth week of fetal development, a group of cells come together to form a structure called the notochord. The notochord defines the vertical mid-line of the body, and the spinal column develops around it. Normally, as development progresses, the noto-chord degenerates and disappears, except for small bits that become part of the disks between the spinal vertebrae. Chordomas are believed to develop from pieces of noto-chord that, for some reason, do not break down as they should. Over many years, these harmless bits of notochord transform and become malignant, forming chordomas.

Symptoms of chordoma depend on where the tumor is located. They are often vague and similar to symptoms of other tumors or even other conditions. Tumors located at the base of the skull may cause headaches, difficulty swallowing, or seizures depending on how much they have invaded the bones of the skull. Tumors located on the sacrum can cause general low back pain or difficulty with bowel and bladder control.

Diagnosis

Diagnosis has two parts: first, determining that the patient has a central nervous system tumor and where it is located, and second, determining what type of tumor it is. It is not easy to diagnose either of these.

A battery of tests is used to diagnose chordomas. A basic neurological examination tests the patient's reflexes, vision, hearing, senses of touch and smell, mental acuity, orientation, memory, and head and neck movements. If the results of the test indicate central nervous system dysfunction, the patient is usually referred to a neurologist (specialist in the central nervous system).

Several different scans are done to locate the tumor. Two of the most common are the computed tomography (CT or CAT) scan and magnetic resonance imaging (MRI). A CT scan uses x-ray images taken from many angles and computer reconstruction to show parts of the body in cross section. This helps to locate and estimate the size the tumor, and provides information on whether it can be surgically removed. MRI uses magnets and radio waves to create more detailed cross-sectional scans than computed tomography. There are many variations on these two scans that use dyes or radioactive materials to provide information about blood flow around the tumor and help determine whether the tumor can be surgically removed.

Treatment team

A neurosurgeon (a surgeon that specializes in the nervous system) will most likely lead the treatment team. A radiologist that specializes in nervous system radiology will interpret CT and MRI scans. Depending on the treatment plan, other members of the team may include a radiation oncologist (a specialist in radiation therapy), radiation technicians, and nurses with special training in assisting cancer patients.