NCIt synonyms : Ewing's Sarcoma, Osseous; Skeletal Ewing's Sarcoma; Osseous Ewing's Sarcoma; Bone Ewing's Sarcoma; Skeletal Ewing's Tumor; Ewing's Sarcoma of Bone; Osseous Ewing's Tumor; Ewing s Sarcoma of Bone;
NCIt definition : A small round cell bone tumor that lacks morphologic, immunohistochemical, and electron
microscopic evidence of neuroectodermal differentiation. It represents one of the
two ends of the spectrum called Ewing sarcoma/peripheral neuroectodermal tumor. It
often affects the diaphysis or metaphyseal-diaphyseal portion of long bones. Clinical
findings include pain and a mass in the involved area. Fever, anemia, leukocytosis,
and an increased sedimentation rate are often seen. X-ray examination reveals osteolytic
lesions. The prognosis depends on the stage, anatomic location, and size of the tumor.;