Question
| A. |
Osteosarcoma |
| B. | Ewing sarcoma |
| C. |
Multiple Myeloma |
| D. |
Chondroblastoma |
|
Correct Answer � B Explanation |
 |
Answer B) Ewing sarcoma
Explanation: The answer can be A) Osteosarcoma and B) Ewing sarcoma because an 8-year-old child present with fever found in both.
But the site i.e md-thigh rules out Osteosarcoma. Osteosarcomas typically occur at the metaphysis of long bones.
Ewing sarcoma
Ewing sarcomas are the second most common malignant primary bone tumors of childhood after osteosarcoma, typically arising from the medullary cavity with the invasion of the Haversian system.
Epidemiology
Ewing sarcoma typically occurs in children and adolescents and has a slight male predilection (M: F 1.5:1)
Location
lower limb: 45%
femur most common
pelvis: 20%
upper limb: 13%
spine and ribs: 13%
the sacrococcygeal region most common 4
skull/face: 2%
Plain radiograph and CT
The appearance of these tumors is very variable, but they usually have clearly aggressive appearance. Common findings include 2,14:
permeative: 76%
lamellated (onion skin) periosteal reaction: 57%
sclerosis: 40%
They occasionally demonstrate other appearances, including Codman triangles, spiculated (sunburst) or thick periosteal reaction and even bone expansion or cystic components.
Soft tissue calcification is uncommon, seen in less than 10% of cases
MIC2 is a specific marker for ewing’s sarcoma and peripheral primitive neuroectodermal tumors.