Bone Cancer

Question 1

Bone tumours: which is

Most common >10y
<10y

Both more common in..

Answer 1

> 10y Osteosarcoma
<10y Ewing

Both more common in adolescence

Question 2

Osteosarcoma features

Cell
Predisposition 
Site
Presentation 
Radiographic
Ddx
Metastases 
Treatment 
Outcome with & without metastases

Answer 2

Spindle cell - produces osteoid
Retinoblastoma, Li-Fraumeni, Paget, Radiotherapy
Metaphyses of long bones
Local pain and swelling; often hx of injury
Sclerotic destruction( less commonly lytic); sunburst pattern
Ewing sarcoma, osteomyelitis
Lungs & bones
Chemotherapy, surgery of primary tumour
Without mets 70% cured; with mets <20%

Question 3

Ewing features 
Cell
Predisposition 
Site
Presentation 
Radiographic findings
Ddx
Metastases 
Treatment 
Outcome

Answer 3

Undifferentiated small round blue cell, prob neural origin
No known
Diaphyses of long bones
Local pain, swelling; fever
Primarily lytic multilamin periosteal reaction (onion skinning)
OM, eosinophilic granuloma, lymphoma, Neuroblastoma, rhabdomyosarcoma
Lungs & bones
Chemotherapy, RT +/- Surg
Without mets 60%; with mets 20-30%