Types of Chordoma
Conventional or Classic
These are the most common type of chordoma, accounting for roughly 80 - 90% of chordoma cases. They are generally slow-growing.
Chondroid chordoma behave similarly to conventional chordoma and account for about 15% of chordomas. They may contain cartilaginous material and be hard to distinguish from chondrosarcomas, except that chondroid chordoma expresses brachyury, whereas chondrosarcomas do not.
These are more aggressive, faster-growing, and more likely to metastasize than Conventional or Chondroid chordoma. They are rare, accounting for only about 5% of chordoma, and they occur most often in pediatric patients. Dedifferentiated chordoma can have the loss of the INI-1 gene.
This is a newly identified subtype. Poorly differentiated chordoma are rare and are more aggressive and faster-growing than Conventional chordoma. They are characterized by the loss of the INI-1 gene, and they occur most often in young adult and pediatric patients. They are most often skull-base tumors.