Osteoscarcama
12 your old male with osteosarcoma distal femur
Step 4: Imaging
Objective :
Recognize features of an abnormal X-ray
This line across the tibia is the normal growth plate. It somewhat resists tumour spread, depending on the pathology, and you can see this tumour has not grown past it.
CloseThe tumour is extending beyond the bone into the soft tissues to produce this soft tissue mass. This is a sign of an aggressive tumour.
CloseThe tumour is radiodense and shows up as this white area in the bone. The density is due to the abnormal bone (‘malignant osteoid’) being laid down by the tumour cells.
CloseWhat is the most likely diagnosis?
Osteosarcoma
Tip 6Yes. This X-ray has many hallmarks of Osteosarcoma : New bone formation, a Codman’s triangle, a soft tissue mass and a poorly defined margin.
CloseInfection
Tip 7This is possible, but not the most likely. Infection can mimic malignant tumours, so it will need to be carefully ruled out. Blood tests such as a CBC and CRP can help.
Close