Radiograph onion skinning Ewing sarcoma

"Onion skin" periosteal reaction AP (A) and lateral (B) view of the distal femur (arrows) in a 15-year-old female child with Ewing sarcoma. Multiple layers of periosteal reaction simulate the appearance of the layers of an onion's skin. Note the disruption of the outermost layer and the soft tissue mass, suggestive of a malignant process.