Stage Grouping Stage IA T1 N0 M0 G1,2 low grade Stage IB T2 N0 M0 G1,2 low grade Stage IIA T1 N0 M0 grade G3,4 high Stage IIB T2 N0 M0 G3,4 high grade Stage III T3 N0 M0 Any G Stage IVA T Any N0 M1a Any G Stage IVB T Any N1 M Any Any G Any T N Any M1b Any G Osteosarcoma Osteosarcoma, accounting for almost 45% of all bone sarcomas, is a spindle cell neoplasm that produces osteoid (unmineralized bone) or bone. About 60% of all osteosarcomas occur in children and adolescents in the second decade of life, and about 10% occur in the third decade of life. Osteosarcomas in the fifth and sixth decades of life are frequently secondary to either radiation therapy or transformation in a preexisting benign condition, such as Paget's disease. Males are affected. | Chapter 094. Soft Tissue and Bone Sarcomas and Bone Metastases Part 5 Stage Grouping Stage IA T1 N0 M0 G1 2 low grade Stage IB T2 N0 M0 G1 2 low grade Stage IIA T1 N0 M0 G3 4 high grade Stage IIB T2 N0 M0 G3 4 high grade Stage III T3 N0 M0 Any G Stage IVA Any T N0 M1a Any G Stage IVB Any T N1 Any M Any G Any T Any N M1b Any G Osteosarcoma Osteosarcoma accounting for almost 45 of all bone sarcomas is a spindle cell neoplasm that produces osteoid unmineralized bone or bone. About 60 of all osteosarcomas occur in children and adolescents in the second decade of life and about 10 occur in the third decade of life. Osteosarcomas in the fifth and sixth decades of life are frequently secondary to either radiation therapy or transformation in a preexisting benign condition such as Paget s disease. Males are affected times as often as females. Osteosarcoma has a predilection for metaphyses of long bones the most common sites of involvement are the distal femur proximal tibia and proximal humerus. The classification of osteosarcoma is complex but 75 of osteosarcomas fall in the classic category which include osteoblastic chondroblastic and fibroblastic osteosarcomas. The remaining 25 are classified as variants on the basis of 1 clinical characteristics as in the case of osteosarcoma of the jaw postradiation osteosarcoma or Paget s osteosarcoma 2 morphologic characteristics as in the case of telangiectatic osteosarcoma small cell osteosarcoma or epithelioid osteosarcoma or 3 location as in parosteal or periosteal osteosarcoma. Diagnosis usually requires a synthesis of clinical radiologic and pathologic features. Patients typically present with pain and swelling of the affected area. A plain radiograph reveals a destructive lesion with a moth-eaten appearance a spiculated periosteal reaction sunburst appearance and a cuff of periosteal new bone formation at the margin of the soft tissue mass Codman s triangle . A CT scan of the primary tumor is best for defining bone .
