<prompt> Soap bubble appearance is seen inGiant cell tumourOsteogenic sarcomaEwings sarcomaOsteoid osteoma  <response>: Giant cell tumour 181 -Apleys 8th Soap-bubble appearance due to ridging of the surrounding bone in Giant cell tumourX-Ray Appearance Osteosarcoma - Sunray appearance, Codmans triangle tumour new bone Ewings tumour - Onion - peel appearance Chondrosarcoma - Mottled calcification within the tumour Simple Bone cyst - Well defined lobulated, radio lucent zone in the metaphysis or diaphysis of bone Osteo chondroma - Large lesion shows Cauliflower appearance and degeneration and calcification in the centre of the cartilage cap 