Chordoma Cancer: Understanding This Rare Spinal and Skull Bone Cancer

What is Chordoma Cancer?

Chordoma is a rare and slow-growing type of cancer that originates from remnants of the notochord, a structure present in early embryonic development that normally disappears as the spine forms. These cancerous tumors most commonly affect the bones of the spine and the base of the skull. While rare, understanding chordoma is crucial for early detection and effective management. In India, as in the rest of the world, awareness about such rare conditions is growing, encouraging more people to seek timely medical advice.

Chordoma is classified as a type of sarcoma, which is a cancer that affects bone and soft tissues. Specifically, it's considered a bone cancer by many medical professionals. The tumors typically develop in specific locations: the sacrum (the triangular bone at the base of the spine), the clivus (the bone at the base of the skull), and the coccyx (the tailbone).

Causes of Chordoma Cancer

The exact cause of chordoma cancer is not fully understood. However, research points to a few key factors:

Genetic Factors:

• Notochordal Cell Remnants: Chordomas arise from notochordal cells. While these cells are essential during embryonic development, their persistence and subsequent transformation into cancer are not fully explained.
• Brachyury Gene Variation: Approximately 95% of individuals diagnosed with chordoma have a specific variation (SNP) in the brachyury gene. This variation doesn't directly cause chordoma but significantly increases the risk of developing it. For instance, about 2 out of every 1 million people with this genetic variation may develop chordoma.
• Tuberous Sclerosis Complex (TSC): Children born with TSC, a rare genetic disorder, have a higher risk of developing chordoma. It is believed that genetic changes associated with TSC might also play a role in increasing chordoma risk.
• Hereditary Chordoma: In rare instances, chordoma can run in families, often associated with having an extra copy of the brachyury gene.

It is important to note that there are no known lifestyle factors that cause or increase the risk of chordoma. This means that diet, exercise, or environmental exposures are not considered contributing factors.

Symptoms of Chordoma Cancer

Chordoma tumors usually grow very slowly, which means symptoms may not appear for many years. When symptoms do occur, they depend heavily on the tumor's size and location. As the tumor grows, it can press on surrounding tissues, nerves, or organs, leading to various signs:

Common Symptoms by Location:

• Sacral Chordoma (Lower Back):
  • Persistent pain in the lower back or tailbone area, which may worsen over time.
  • A palpable lump or swelling in the lower back.
  • Bowel or bladder control issues (incontinence or difficulty urinating/defecating).
  • Numbness or weakness in the legs or feet.
• Clival Chordoma (Base of Skull):
  • Headaches, often persistent and severe.
  • Vision problems, such as double vision (diplopia), blurred vision, or loss of peripheral vision.
  • Facial pain or numbness.
  • Difficulty swallowing (dysphagia).
  • Hoarseness.
  • Problems with balance or dizziness.
• Spinal Chordoma (Mid-Spine):
  • Pain in the neck or back.
  • Numbness or weakness in the arms or legs.
  • Loss of bowel or bladder control.

It's crucial to remember that these symptoms can be caused by many other, less serious conditions. However, if you experience persistent or concerning symptoms, seeking medical evaluation is essential.

Diagnosis of Chordoma Cancer

Diagnosing chordoma involves a combination of medical history, physical examination, and advanced imaging techniques. The process typically includes:

Medical History and Physical Examination:

Your doctor will ask about your symptoms, their duration, and any relevant family history. A physical exam helps assess your overall health and check for any palpable masses or neurological deficits.

Imaging Tests:

• MRI (Magnetic Resonance Imaging): This is the primary imaging tool for diagnosing chordoma. MRI provides detailed images of soft tissues and bones, helping to determine the tumor's size, location, and extent.
• CT Scan (Computed Tomography): CT scans are useful for visualizing bone detail and can help assess the tumor's relationship with surrounding bony structures.
• PET Scan (Positron Emission Tomography): A PET scan may be used to check if the cancer has spread to other parts of the body (metastasis) or to assess the tumor's activity.

Biopsy:

A definitive diagnosis is made through a biopsy, where a small sample of the tumor tissue is removed and examined under a microscope by a pathologist. This confirms the presence of chordoma cells and helps differentiate it from other types of tumors.

Treatment Options for Chordoma Cancer

Treatment for chordoma is complex and depends on several factors, including the tumor's location, size, stage, and the patient's overall health. The primary goal is to remove as much of the tumor as possible while preserving neurological function.

Surgery:

Surgery is the main treatment for chordoma. The goal is to achieve a complete resection (removal) of the tumor. However, due to the tumor's location near critical structures like the brainstem, spinal cord, and major nerves, complete removal can be challenging and may require specialized surgical techniques, sometimes involving multiple surgeries over time.

Radiation Therapy:

Radiation therapy is often used after surgery, especially if there's a risk of the cancer returning or if complete removal was not possible. High-energy rays are used to kill any remaining cancer cells. Proton therapy, a type of radiation that precisely targets tumor cells while sparing surrounding healthy tissue, is often preferred for chordoma due to its location.

Chemotherapy:

Chemotherapy is generally less effective for chordoma compared to surgery and radiation. It is typically not the primary treatment but may be considered in specific cases, especially if the cancer has spread widely.

Targeted Therapy and Clinical Trials:

Research is ongoing to develop targeted therapies that specifically attack cancer cells. Patients may have the opportunity to participate in clinical trials investigating new treatment approaches.

Prognosis and Survival Rates

The prognosis for chordoma varies significantly among individuals. Factors influencing survival include the tumor's stage, location, the success of surgical removal, and the patient's overall health and age. Survival data is often based on past patient experiences and may not fully reflect the outcomes with newer treatments.

Five-Year Relative Survival Rates (2011-2017 data):

• Localized (cancer hasn't spread): 86%
• Regional (cancer spread to nearby areas): 85%
• Distant (cancer has metastasized): 61%

It's important to understand that these are statistical averages. Many people with chordoma live much longer than five years, and individual experiences can differ greatly. Advances in treatment continue to improve outcomes.

Prevention of Chordoma Cancer

Currently, there are no known methods to prevent chordoma cancer, as its development is primarily linked to genetic factors and embryonic cell remnants rather than lifestyle choices. The focus remains on early detection and effective management.

When to Consult a Doctor

You should consult a doctor if you experience any of the persistent symptoms mentioned earlier, especially:

• Unexplained, persistent pain in the lower back, tailbone, or head/neck region.
• Changes in bowel or bladder function.
• New or worsening vision problems.
• Unexplained headaches or neurological symptoms.

Prompt medical attention is key to achieving the best possible outcome.

Frequently Asked Questions (FAQ)

Q1: Is chordoma cancer curable?

Chordoma can be challenging to cure completely due to its location and tendency to recur. However, with aggressive treatment, including surgery and radiation, long-term control and remission are possible for many patients. The goal is often to manage the condition effectively and improve quality of life.

Q2: Can chordoma spread to other parts of the body?

Yes, chordoma can metastasize (spread) to other parts of the body, although this is less common than with some other cancers. Around 30%-40% of chordoma tumors may spread, often to the lungs or liver. However, even with metastasis, treatment options are available.

Q3: Is chordoma a type of bone cancer?

Yes, chordoma is classified as a rare type of bone cancer, specifically a sarcoma that affects bone and soft tissue.

Q4: What is the role of genetics in chordoma?

Genetics plays a significant role. While most cases are sporadic, a variation in the brachyury gene is found in about 95% of patients. In rare instances, it can be hereditary, linked to genetic conditions like Tuberous Sclerosis Complex or extra copies of the brachyury gene.

Q5: How is chordoma different from other spinal tumors?

Chordoma is unique because it arises from notochordal remnants and typically occurs at the skull base, sacrum, or coccyx. Its slow-growing nature and specific genetic associations also distinguish it from other types of spinal tumors, which can have different origins and growth patterns.