Outlinesreqrments and time alltio 'cancellous'osteoma showing predominantly a lamellar structure Giant cell tumor Giant cell tumor is a locally aggressive neoplasm composed of connective tissue.giant cells and stromal cells. 10min Presentations Earliest manifestations include pain,local swelling.limitation of motion and pathologic fractures. The sites affected most frequently are the long tubular bones.bones about the knee,spine,and innominate bone. Diagnosis 10min On radiographs.the long and short tubular bones reveal eccentric osteolytic lesions extending to the subchondral bone A delicate trabecular pattem results from subsequent cortical thinning and expansion. Violation of the cortical surface and spread into contiguous soft tissues is striking evidence of the aggressiveness of some giant cell tumors. Tumors involving the flat bones may also be osteolytic.vertebral collapse may occur if the spine is affected. Osteoid osteoma 10min Osteoid osteoma is a benign osteoblastic tumor composed of a central coreof vascular osteoid tissue and a peripheral zone of sclerotic bone. The precise relationship of osteoid osteoma to a second lesion of bone.the osteoblastoma,is not well understood. The tumors are painful and may be accompanied by soft tissue swelling andOutlines, requirements and time allocation ⚫ 'cancellous' osteoma showing predominantly a lamellar structure. Giant cell tumor ⚫ Giant cell tumor is a locally aggressive neoplasm composed of connective tissue, giant cells and stromal cells. Presentations ⚫ Earliest manifestations include pain, local swelling, limitation of motion and pathologic fractures. ⚫ The sites affected most frequently are the long tubular bones, bones about the knee, spine, and innominate bone. Diagnosis ⚫ On radiographs, the long and short tubular bones reveal eccentric osteolytic lesions extending to the subchondral bone ⚫ A delicate trabecular pattern results from subsequent cortical thinning and expansion. ⚫ Violation of the cortical surface and spread into contiguous soft tissues is striking evidence of the aggressiveness of some giant cell tumors. ⚫ Tumors involving the flat bones may also be osteolytic; vertebral collapse may occur if the spine is affected. Osteoid osteoma ⚫ Osteoid osteoma is a benign osteoblastic tumor composed of a central core of vascular osteoid tissue and a peripheral zone of sclerotic bone. ⚫ The precise relationship of osteoid osteoma to a second lesion of bone, the osteoblastoma, is not well understood. ⚫ The tumors are painful and may be accompanied by soft tissue swelling and tenderness. . 10min 10min 10min