Diagnostic assessment and interpretation:
Lab investigation including CBC showed anemia. X rays showed intramedullary lesion at mid shaft femur with onion skin type of periosteal reaction and multiple drill holes on the cortex (Fig 2). MRI showed an enhanced heterogeneous mass at shaft of the femur with soft tissue extension occupying antero- medial and lateral compartment, which raised a high suspicion of malignant tumor. (Fig 3). Core needle biopsy was performed and histology revealed Ewing’s sarcoma.