2: Bone and Cartilage Sarcoma
This is the other big group of sarcomas. The most common types are osteosarcoma and Ewing's sarcoma, although a multitude of other types exist.
General Features
Bone tumours may be lytic or sclerotic (or sometimes both). Metastasis to bone is far more common than primary bone tumours and is always an important differential diagnosis.
Lytic lesions may include:
- Lytic metastases
- Myeloma (most common primary bone tumour) or solitary plasmacytoma
- Ewing sarcoma
- Chondrosarcoma
- Giant cell tumour of bone
- Adamantinoma
- Chordoma
Sclerotic lesions may include:
- Sclerotic bone metastases
- Paget's disease
- Osteosarcoma
- Benign tumours (osteoid osteoma, osteoblastoma)
In children, the most common primary tumours are:
- Osteosarcoma
- Ewing sarcoma
In adults, the most common primary tumours are:
- Myeloma
- Osteosarcoma (often secondary to Paget's or radiotherapy)
- Ewing sarcoma is rare in the adult age group (< 20% of cases)