Ewing Sarcoma

  • Etiology: malignant small round blue cell tumor
  • Imaging: occurs in both long + flat bones, meta/diaphyseal medullary mass with permeating cortical destruction, onion skin or sunburst perisoteal reaction, large extraosseous soft tissue mass, in spine mimics other vertebral body tumors with vertebral body collapse and intradural and extradural spinal extension
  • Complications: metastasis to lung
  • Clinical: occurs in 10-20 year olds, can mimic osteomyelitis + be associated with leukocytosis / fever / increased sedimentation rate, when in rib has eponym of Askin tumor

Cases of Ewing Sarcoma

Radiograph and CT of Ewing sarcoma of the spine
Lateral radiograph of the spine shows collapse of the T12 vertebral body. Sagittal 2D reconstruction and axial CT without contrast of the T12 vertebral body in bone windows shows a permeative destructive process affecting it. Axial CT without contrast of the abdomen at the T12 level shows a large left-sided paraspinal soft tissue mass.
Radiograph of Ewing Sarcoma
AP radiograph of the right hip shows a permeative appearance to the medullary portion of the proximal femur with cortical destruction and diffuse periosteal reaction.
CT of Ewing sarcoma of the rib
Axial CT with contrast of the chest shows a large heterogenous non-enhancing soft tissue mass centered around the posterior aspect of the right 11th rib. 3D CT reconstruction better demonstrates the lesion’s origin from the right 11th rib.
Pathological image of Ewing sarcoma of the rib
Pathological image shows a tumor which was brown and grossly necrotic and was seen to be located predominantly in the soft tissues and not in the rib.