Chordoma and Cancer

Following a chordoma diagnosis, patients may wonder about its connection to the ominous "C" word - cancer. Unfortunately, a chordoma is considered a type of malignant bone cancer. In this article, we will discuss chordoma formation, its various classification systems, and impact on prognosis.

A chordoma is a rare cancer that starts in cells of the notochord. The notochord is a rod-like structure that supports the baby during early development in the womb. As the baby grows, most of the notochord disappears but some cells can remain in certain areas of the body, like the base of the skull and lower back. These cells can become cancerous due to genetic mutations and divide uncontrollably to form a tumor. A tumor that develops from such cells is called a chordoma. There are no known dietary or lifestyle risk factors for chordoma formation.

Yes, a chordoma is a malignant bone cancer. Unlike other types of bone cancers that tend to occur in the legs and arms, chordomas commonly occur in the base of the skull, tailbone, and the spine. Although they are slow growing, chordomas can cause damage to the nearby tissues and bones. They are also known to recur, making their treatment challenging.

Although rare, chordomas can metastasize. Metastasis is the spread of cancer from the original (primary) site to other parts of the body. The cancer cells can spread through the body’s circulation system and form new tumors in other organs or tissues. Chordoma metastases commonly occur in the lungs, brain, and bone.

It is important to remember that not all chordomas will metastasize. The risk of metastasis depends on the size, location, and subtype of the tumor. Early detection and treatment are crucial to improve the chances of controlling the spread of the disease. The treatment of metastatic chordomas involves a combination of surgery, radiation therapy, and rarely, chemotherapy.

Grading of a tumor is a way to determine how aggressive it is. It helps to select suitable treatment options and predict the outcome.

If your doctor suspects a chordoma, they will perform a biopsy, in which a small sample of the tumor is collected and examined under a microscope. The biopsy results will also include the grade of the tumor.

The World Health Organization (WHO) classifies chordomas into 3 grades based on the appearance of the cells under the microscope.

• Grade 1 (low grade): The tumor cells look very similar to normal cells and are growing slowly.
• Grade 2 (intermediate grade): The tumor cells look less like normal cells and are growing at a moderate rate.
• Grade 3 (high grade): The tumor cells look very different from normal cells and are growing quickly.

The staging of chordoma is determined by the grade of the tumor, how invasive it is, and whether it has spread to other parts of the body. The most used staging system for chordoma is the Enneking staging system, which stages chordomas into:

• Stage 1A: Low-grade tumor, located only within the vertebra, with no spread to other distant parts of the body.
• Stage 1B: Low-grade tumor, invaded surrounding tissue, with no spread to other distant parts of the body.
• Stage 2A: High-grade tumor, located only within the vertebra, with no spread to other distant parts of the body.
• Stage 2B: High-grade tumor, invaded surrounding tissue, with no spread to other distant parts of the body.
• Stage 3: Tumor has spread to other distant parts of the body.

The higher the stage, the more severe and aggressive the tumor is, and the worse the overall prognosis in general.

To determine the level of invasion of surrounding tissues, computed tomography (CT) and magnetic resonance imaging (MRI) scans of the chordoma are needed. To discover spread to distant parts of the body, CT scans of the chest and abdomen along with positron emission tomography (PET) scans are useful to look for signs of metastases.

• Chordomas develop from abnormal remnant cells during development in the womb.
• Chordomas are rare bone cancers that are locally aggressive but rarely spread to distant organs and tissues.
• The grade of the chordoma is determined by a biopsy and examination of the tumor sample under a microscope.
• The stage of the chordoma is determined by the grade of the tumor, its invasion into surrounding bone and tissues, and its spread to distant parts of the body. The higher the stage, the more severe the tumor.

• National Cancer Institute: Chordoma
• Chordoma Foundation
• NIH Genetic & Rare Diseases (GARD) Center: Chordoma
• Cancer Net
• American Cancer Society