Comparison of various demographic, location, and imaging features of chordomas with those of the most common imaging differential diagnoses
| Chordoma | GCT | Chondrosarcoma | Plasmacytoma | |
|---|---|---|---|---|
| Age at diagnosis (range) (peak yr) | 40–60 | 20–30 | 30–70 | 30–60 |
| Most common location in mobile spine | Cervical | Lumbar (sacrum much more common) | Lumbar | Thoracic |
| Commonly involves posterior elements | – | + | + | + |
| Intratumoral calcification | Amorphous | – | Rings and arcs | – |
| T2WI | ↑↑ | ↓→ | ↑ | ↑ |
| Extraosseous extension | + | + | + | – |
| Characteristic feature | Dumbbell or mushroom shape | Lytic lesion without sclerotic rim; fluid-fluid levels | Intratumoral chondroid matrix | Minibrain, soap bubble |
Note:—GCT indicates Giant cell tumor; –, features absent; +, features present; ↓→, hypo- to iso-intense intralesional signal; ↑, hyperintense intralesional signal.