Outlines requirements and time allocation 10min Diagnosis Radiographically.these lesions appear radiolucent and are located centrally, with cortical thinning and mild expansion of the bone CT scanning and MR imaging with contrast enhancement reveal presence of fluid within the lesion Osteosarcoma Osteosarcoma is a malignant neoplasm of bone composed of proliferating 10min tumor cells that in most instances immature bone Pathological Types intramedullary or central.intracortical,surface.periosteal.or parosteal high grade or low grade single or multicentric Diagnosis On the radiograph,the tumor may be purely lytic or sclerotic,or a mixture of the two a very thin periosteal reaction overlying the lesion with very little evidence of new bone formation The sclerotic osteogenic sarcomas may produce a region of dense sclerosis with loss of the inner cortical margins .'sunburst'appearanceOutlines, requirements and time allocation Diagnosis ⚫ Radiographically, these lesions appear radiolucent and are located centrally, with cortical thinning and mild expansion of the bone ⚫ CT scanning and MR imaging with contrast enhancement reveal presence of fluid within the lesion Osteosarcoma ⚫ Osteosarcoma is a malignant neoplasm of bone composed of proliferating tumor cells that in most instances produce osteoid or immature bone Pathological Types ⚫ intramedullary or central, intracortical, surface, periosteal, or parosteal ⚫ high grade or low grade single or multicentric Diagnosis ⚫ On the radiograph, the tumor may be purely lytic or sclerotic , or a mixture of the two ⚫ a very thin periosteal reaction overlying the lesion with very little evidence o f new bone formation ⚫ The sclerotic osteogenic sarcomas may produce a region of dense sclerosis with loss of the inner cortical margins ⚫ ‘sunburst' appearance 10min 10min