Definition
A malignant small round-cell tumour of bone and soft tissue, usually affecting children and adolescents.
Common sites
- Diaphysis of long bones
- Pelvis
- Ribs
Clinical features
- Pain and swelling
- Fever and raised inflammatory markers may mimic infection
- Constitutional symptoms in some patients
Imaging
- Permeative destructive lesion
- Layered or onion-skin periosteal reaction may occur
- MRI for local staging
- CT chest for metastases
Diagnosis
- Biopsy through a specialist tumour unit pathway
- Small round blue cells with characteristic translocation, commonly EWSR1-related
Treatment
- Neoadjuvant chemotherapy
- Local control by surgery and/or radiotherapy
- Adjuvant chemotherapy
Prognosis
Depends on metastatic disease, tumour site, size and response to treatment.
Diagram
