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Understanding chordoma

Children and young adults

Chordoma in children and young adults is rare, with patients under the age of 20 years old accounting for only 5 percent of all chordoma cases. The skull base and cervical spine are the most common locations of chordoma in children and young adults, and the number of females diagnosed is slightly higher than the number of males. The poorly differentiated type of chordoma is more common in patients under the age of 35 than it is for older adults.


If you or your child might have chordoma, the most important thing to do is to find a medical center with a team of experts who have experience caring for chordoma patients. For diagnosis, this team should include a radiologist and pathologist with chordoma experience.

While imaging tests like an MRI or CT scan can show the possibility of a chordoma, a definitive diagnosis can only be made by a pathologist who examines a sample of the tumor tissue under a microscope. The process of removing tumor tissue for analysis is called a biopsy. A biopsy or surgery to confirm the diagnosis should only be done by a team with chordoma expertise because, if not done properly, these procedures can cause the chordoma to spread.

The pathologist will perform immunohistochemistry (IHC) testing to look for protein markers, such as brachyury, which help distinguish chordoma from other tumors. Pathologists also determine the type of chordoma with IHC testing. A specific kind of IHC test should be done for pediatric, adolescent, and young adult patients to help determine whether the tumor is poorly differentiated. This test looks to see whether a protein called INI1 is present or absent in the tumor cells. INI1 is typically absent in poorly differentiated chordoma and on rare occasions in conventional or dedifferentiated tumors as well. This is also called INI1 loss, or INI1 negative.

From the Chordoma Foundation Medical Advisory Board

The Chordoma Foundation Medical Advisory Board suggests that chordoma patients under 35 years of age, or whose tumors are growing unusually fast, have their tumors tested for loss of INI1, either through immunohistochemistry (IHC) or genomic testing.

If tissue is not available for testing, the possibility of a biopsy to obtain tissue for this testing should be discussed with a doctor who has experience treating chordoma, carefully weighing the potential risks of biopsy. Interpretation of the testing should be done by a pathologist who has experience diagnosing chordoma.

Types of chordoma

The WHO Classification of Soft Tissue and Bone Tumours (5th edition, April 2020) defines the following three types of chordoma. These types are based on the histological appearance and characteristics of the tumor cells.


  • Most common form of chordoma

  • Typically slow-growing

  • Composed of a unique type of cell with a “bubbly” appearance

  • Expresses the brachyury protein, which is a hallmark of chordoma and distinguishes conventional chordoma from other tumors like chondrosarcoma

  • Chondroid chordoma, previously a separate type, is now considered to be a kind of conventional chordoma


  • Very rare subtype that occurs in 5 percent or less of patients

  • Typically more aggressive, faster-growing, and more likely to metastasize than conventional chordoma

  • Can have different treatment options than conventional chordoma, including chemotherapy

  • Appears as a mix of conventional chordoma cells that express brachyury and cells that resemble high-grade sarcoma and do not express brachyury

Poorly differentiated

  • Very rare subtype officially recognized for the first time in the most recent (2020) edition of the WHO classifications

  • Typically more aggressive, faster-growing, and more likely to metastasize than conventional chordoma

  • More common in younger patients as well as those with skull base and cervical tumors

  • Can have different treatment options than conventional chordoma, including chemotherapy

  • Defining characteristic is deletion of a gene called SMARCB1, or INI1


Chordoma is less common in patients under the age of 35 than it is for older adults, and it affects very important and complex parts of the body. Appropriate treatment requires very specialized care provided by multiple types of doctors. This team approach involving multiple specialists is called multidisciplinary care. It is typically only found at larger hospitals, sometimes called referral centers, which see large numbers of patients.

Experts recommend your or your child’s chordoma treatment team include the following specialists:

  • Pathologist
  • Radiologist
  • Surgeon
  • Radiation oncologist
  • Medical oncologist
  • Palliative and pain medicine specialist

The Chordoma Foundation has created a Doctor Directory as an informational resource for patients and caregivers. The Directory includes the names of physicians who have given their permission to be identified publicly and who meet inclusion criteria developed by the Chordoma Foundation’s Medical Advisory Board.

Search the Doctor Directory

Pediatric vs. chordoma expertise

For children 18 years old and younger, it is important that the team of specialists treating your child includes both chordoma specialists and pediatric specialists. There are very few doctors who have expertise with pediatric chordoma specifically. Chordoma experts suggest consulting with doctors with chordoma experience first and then talking with those doctors about how they will work together with a pediatric specialist.

Pediatric treatment also requires facilities and support staff specific to children and adolescents. Operating rooms, recovery and intensive care units, and infusion clinics all have specialized equipment for children. In addition, the nurses, support staff, and others in pediatric care units have specialty training and in many cases can offer services that are not available to patients elsewhere.

Participate in a study

Children and young adults affected by chordoma can participate in the following studies. By participating in these studies, you will not only advance chordoma research in general, but you can also receive personalized treatment options based on recent research discoveries.

Connect with others and get support

Talking with others can help you understand and navigate this journey. There are a number of ways to connect with other patients and families and get one-on-on support.

Peer Connect

Our free, confidential peer-to-peer support program connects anyone touched by chordoma with another person whose experiences with chordoma are similar. Trained Peer Guides are available to support patients who are newly diagnosed, patients in active treatment, survivors, caregivers, family members, or friends.

Meet our Peer Guides

Chordoma Connections

Our private online community is a place where anyone affected by chordoma can come together to exchange information, share experiences, and support one another.

Join Chordoma Connections

Virtual support groups

We offer groups for patients and survivors (any age), caregivers and co-survivors, and adolescent and young adult (AYA) survivors. The AYA group is led by a young adult chordoma survivor and is open to patients and survivors ages 16 to 30 years old. All groups meet virtually on a monthly basis and are a great source of comfort and camaraderie.

Register for a group

Chordoma Survivors on Facebook

Patients, survivors, and family members can connect with others in a private group on Facebook hosted by members of the chordoma community. This close-knit community exists to help answer questions, share personal experiences, offer guidance, and serve as encouragement throughout your journey with chordoma.

Join the Facebook group

Pediatric chordoma research

To ensure that the youngest members of our community benefit from the rapid advances being made for chordoma – and cancer more generally – the Chordoma Foundation is making pediatric chordoma research a top priority.

By collecting precious pediatric chordoma tumor samples for research, testing drugs against pediatric chordoma tumor models, and finding new vulnerabilities in pediatric chordoma, our research is accelerating the development of better treatments and improving outcomes for this underserved patient population.

Learn more about the Pediatric Chordoma Initiative

Contact a Chordoma Foundation Patient Navigator

Chordoma Foundation Patient Navigators provide personalized information and support to anyone affected by chordoma, anywhere in the world, at any stage of their journey. Your Patient Navigator will use their extensive knowledge of chordoma to help answer your questions, provide information about treatment guidelines, help you find qualified doctors, talk with you about side effects, and connect you with others in the chordoma community who have been through a similar journey.