Radiograph, magnetic resonance imaging, and bone scan of a patient with localized osteosarcoma of the left proximal tibia

(A) Radiograph of tumor in proximal tibia showing aggressive periosteal reaction with sunburst appearance.
(B) Postcontrast sagittal T1 MRI image demonstrating a large soft tissue mass associated with the primary tumor.
(C) Total body bone scan showing increased radiotracer uptake confined to the primary tibial mass.