Chordoma is a rare bone cancer that demands a highly specialized treatment approach, combining surgery, advanced radiation techniques, and in some cases, investigational drugs. Because these tumors grow near critical structures like the spinal cord and brain, achieving complete removal while preserving function remains one of the greatest challenges in oncology.

How Treatment Aims to Control a Complex Cancer

Treating chordoma is fundamentally about removing the tumor as completely as possible and preventing it from returning. Unlike many cancers, chordoma does not respond well to standard chemotherapy, which means the backbone of treatment relies on surgical removal and high-dose radiation therapy. The ultimate goal is to achieve local control—keeping the tumor from growing back in the same place—while preserving as much normal function as possible for the patient.

What makes chordoma treatment particularly challenging is where these tumors grow. About 35 percent develop at the base of the skull, another 35 percent in the sacrum at the lower spine, and 30 percent along the mobile spine. All of these locations sit dangerously close to the spinal cord, brainstem, major blood vessels, and vital nerves. This means surgeons must balance the need for complete tumor removal against the risk of damaging structures that control movement, sensation, breathing, and other essential functions.

Treatment decisions depend heavily on several factors: the tumor’s exact location, its size, whether it has spread to other parts of the body, the patient’s age and overall health, and whether this is a first diagnosis or a tumor that has come back. Most newly diagnosed patients will undergo a combination of surgery and radiation. For those whose tumors return or spread—which happens in 30 to 40 percent of cases—drug therapy may also be considered, though options remain limited.

Because chordoma is so rare, affecting only about 1 in 1 million people each year, it is essential that patients receive care at specialized centers where surgeons, radiation oncologists, and medical oncologists have experience with this disease. Treatment guidelines published in 2015 in The Lancet Oncology emphasize that a team-based approach, involving multiple specialists working together, gives patients the best chance for a good outcome.

Standard Treatment: Surgery and Radiation as the Foundation

Surgery is the most important treatment for chordoma and the only one that offers a potential cure. The surgical technique that provides the best outcome is called en bloc resection, which means removing the entire tumor in one piece, surrounded by a margin of healthy tissue. This approach is critical because cutting through the tumor or leaving even tiny fragments behind dramatically increases the chance that it will grow back. Studies show that patients who undergo complete removal with negative margins—meaning no cancer cells are seen at the edges of the removed tissue—have the longest periods without recurrence.

Unfortunately, achieving en bloc resection is extremely difficult for chordomas. The tumors often wrap around nerves, blood vessels, and other structures that cannot be sacrificed. In cases where the tumor is located in the skull base near the brainstem, or in the sacrum near the spinal cord, complete removal may be impossible without causing severe disability. In these situations, surgeons may perform a debulking procedure, removing as much of the tumor as safely possible, or use curettage, a technique where the tumor is scraped out using a specialized tool. After curettage, surgeons sometimes apply bone cement, a chemical called polymethyl methacrylate, which heats up as it hardens and can kill any remaining cancer cells left in the bone.

Recovery from chordoma surgery varies greatly depending on the tumor’s location. Patients who have surgery at the base of the skull may experience changes in vision, facial sensation, or swallowing. Those who have sacral tumors removed may face challenges with bowel or bladder control. Rehabilitation, including physical therapy, occupational therapy, and sometimes speech therapy, plays a crucial role in helping patients regain function and adapt to any permanent changes.

Following surgery, most patients receive radiation therapy. Radiation therapy uses high-energy beams to destroy any cancer cells that may remain after surgery. Chordomas are resistant to standard doses of radiation, which means they require much higher doses than many other cancers. This creates a challenge because nearby critical structures like the spinal cord and brainstem cannot tolerate such high doses without risk of serious damage.

To deliver the necessary radiation dose safely, doctors use advanced techniques called proton beam therapy or carbon ion therapy. Unlike conventional radiation, which passes through the body and can damage tissues beyond the tumor, proton beams stop precisely at the tumor site, minimizing exposure to surrounding healthy tissue. Proton beam therapy has become the preferred radiation method for chordomas, particularly those at the skull base. Treatment typically involves daily sessions over several weeks, and patients usually tolerate it well, though side effects can include fatigue, skin changes at the treatment site, and depending on the tumor’s location, temporary hair loss, nausea, or changes in swallowing.

For tumors that cannot be removed surgically—because they are too close to vital structures or the patient is not healthy enough for surgery—radiation alone may be used as the primary treatment. In these cases, stereotactic body radiation therapy (SBRT) may be considered if the tumor is small. This technique delivers very precise, high-dose radiation in just a few sessions.

The timing of radiation therapy matters. Most experts recommend starting radiation within a few weeks to months after surgery, once surgical wounds have healed. However, if imaging shows that the tumor was completely removed with clear margins, some doctors may recommend careful monitoring instead of immediate radiation, reserving radiation for later if the tumor shows signs of returning.

It is important to understand that even with the best surgery and radiation, chordomas have a tendency to come back. The five-year survival rate is approximately 50 percent, but survival varies widely depending on the tumor’s location, the completeness of surgical removal, and the tumor’s specific type. Regular monitoring with MRI scans—typically every few months initially, then less frequently over time—is essential for detecting recurrence early, when it may still be treatable.

Treatment in Clinical Trials: Exploring New Therapies

When surgery and radiation are no longer effective—either because the tumor has returned multiple times or has spread to distant organs like the lungs—doctors may turn to systemic therapy, also called drug therapy. This involves treatments that travel through the bloodstream to reach cancer cells throughout the body. Unlike surgery and radiation, which target specific areas, systemic therapy can potentially treat chordoma wherever it has spread.

Currently, no drugs have been officially approved by regulatory agencies like the U.S. Food and Drug Administration (FDA) or the European Medicines Agency (EMA) specifically for treating chordoma. However, doctors can prescribe certain drugs “off-label,” meaning they use medications approved for other cancers to treat chordoma. Because insurance companies and health systems often do not cover off-label use, these treatments can be expensive and difficult to access. Some patients are able to receive experimental drugs by participating in clinical trials, which are carefully monitored research studies testing new treatments.

The most commonly used drug for advanced chordoma is imatinib, a medication originally developed for chronic myeloid leukemia and gastrointestinal stromal tumors. Imatinib works as a tyrosine kinase inhibitor, blocking specific signals that cancer cells use to grow and divide. It targets proteins called platelet-derived growth factor receptor beta (PDGFR-beta) and epidermal growth factor receptor (EGFR), both of which are often found on chordoma cells. In clinical studies, imatinib has shown benefit primarily in patients whose tumors test positive for these receptors.

Another drug that has shown promise is erlotinib, which specifically targets EGFR. In some cases where chordoma has stopped responding to imatinib—called imatinib-refractory disease—erlotinib has produced partial responses, meaning the tumor has shrunk somewhat. Combination therapy, using two tyrosine kinase inhibitors together or combining a tyrosine kinase inhibitor with another type of drug, is sometimes tried as a second-line approach when initial treatments fail.

Researchers have discovered that many chordomas have abnormalities in the mTOR signaling pathway, a system of proteins that controls cell growth and division. Nearly all sacral chordomas show overactivity in this pathway, which has led to interest in drugs called mTOR inhibitors. These medications, which include drugs like everolimus, work by blocking the mTOR protein and slowing tumor growth. Clinical trials are exploring whether mTOR inhibitors, alone or in combination with other drugs, can help patients with advanced chordoma.

Another area of active research involves immunotherapy, treatments that help the patient’s own immune system recognize and attack cancer cells. One approach being studied is a brachyury vaccine. Brachyury is a protein produced by the TBXT gene, which is found in more than 95 percent of chordomas. The vaccine is designed to train the immune system to recognize brachyury as foreign and destroy cells that make it. Early-phase clinical trials are evaluating the safety and effectiveness of this vaccine approach.

Scientists have also found that about 62 percent of chordomas express a protein called Chondroitin sulfate proteoglycan 4 (CSPG4), also known as the High Molecular Weight Melanoma Associated Antigen. This protein is being studied as a potential target for immune-based therapies, including specialized immune cells engineered to attack chordoma cells displaying this marker.

Clinical trials for chordoma are taking place at major cancer centers in the United States, Europe, and other parts of the world. Phase I trials focus on determining whether a new treatment is safe and what dose should be used. Phase II trials evaluate whether the treatment actually works against the cancer, measuring things like tumor shrinkage and how long patients live without disease progression. Phase III trials compare new treatments against current standard treatments to see which is more effective.

Because chordoma is so rare, recruiting enough patients for clinical trials is extremely challenging. Patients considering a trial should discuss the potential benefits and risks with their oncologist, including possible side effects, how often they will need to visit the treatment center, and whether their insurance or the trial sponsor will cover the costs. Organizations like the Chordoma Foundation maintain databases of active clinical trials and can help connect patients with appropriate studies.

Research continues into understanding the genetic changes that drive chordoma growth. Scientists know that mutations in the TBXT gene play a central role, and that other genes like TSC1, TSC2, PTEN, and CDKN2A are frequently altered in chordoma cells. By identifying these molecular abnormalities, researchers hope to develop drugs that specifically target the unique vulnerabilities of chordoma cells while sparing normal tissue. This approach, called targeted therapy, represents the future of chordoma treatment and offers hope for more effective, less toxic therapies.

Most common treatment methods

• Surgery
  • En bloc resection (removing the entire tumor in one piece with a margin of healthy tissue around it) is the preferred surgical technique and offers the best chance for cure
  • Debulking surgery removes as much tumor as safely possible when complete removal would cause unacceptable damage to nearby structures
  • Curettage uses a spoon-shaped tool to scrape the tumor out of bone, sometimes followed by bone cement application to destroy remaining cancer cells
  • Surgery may be performed in stages, with multiple operations needed depending on tumor location, size, and shape
• Radiation therapy
  • Proton beam therapy delivers high-dose radiation precisely to the tumor while minimizing damage to surrounding critical structures like the brainstem and spinal cord
  • Carbon ion therapy is another advanced radiation technique used primarily in specialized centers in Europe and Japan
  • Stereotactic body radiation therapy (SBRT) may be used for small residual tumors, delivering very precise high doses in just a few treatment sessions
  • Conventional external beam radiation therapy may be used when advanced techniques are not available, though it requires careful planning to protect nearby tissues
  • Radiation is typically given after surgery to destroy any remaining cancer cells, or as primary treatment when surgery is not possible
• Targeted therapy
  • Imatinib is the most commonly used drug for advanced chordoma, particularly when tumors test positive for PDGFR-beta or EGFR receptors
  • Erlotinib has shown benefit in some patients, including those whose tumors have stopped responding to imatinib
  • mTOR inhibitors are being studied in clinical trials for patients with mTOR pathway abnormalities
  • Combination therapy using two tyrosine kinase inhibitors or a tyrosine kinase inhibitor plus an mTOR inhibitor may be considered for treatment-resistant disease
• Immunotherapy
  • Brachyury vaccine is being evaluated in clinical trials to train the immune system to recognize and attack chordoma cells
  • Other immune-based approaches targeting proteins like CSPG4 are in early research stages
• Supportive care
  • Physical therapy helps patients recover movement and strength after surgery
  • Occupational therapy assists with adapting to changes in daily activities and function
  • Pain management using medications, nerve blocks, and other techniques addresses chronic discomfort
  • Rehabilitation services support patients in managing permanent changes such as bowel or bladder dysfunction