Classic history and presentation: The most common primary sites are within the axial skeleton: the sacrum / coccyx, skull base / clivus, and mobile spine.
Prevalence: Incidence of chordomas is about 1 per 1 million, and these tumors comprise 1%-4% of all primary malignant bone tumors.
- Age – Chordomas usually occur in patients older than 40 years (peak incidence at age 50-60 years) and rarely occur in the pediatric population.
- Sex / gender – Chordomas are more common in men.
Grade / classification system: Chordoma typically behaves in a low-to-intermediate grade manner with local recurrences being problematic after surgically treated disease.
There are several chordoma histologic variants –
- Classical chordoma: 97% of all chordoma cases
- Chondroid chordoma: best prognosis
- Dedifferentiated chordoma: worst prognosis
- Poorly differentiated chordoma: defined only recently