Intracortical Osteosarcoma

Intracortical osteosarcoma is the rarest form of osteosarcoma and typically occurs in the young. The authors describe a case of intracortical osteosarcoma arising in the femur of a 44-year-old woman. A diaphyseal location and a typical radiographic appearance, illustrated in this report, distinguish intracortical osteosarcoma from conventional (intramedullary) osteosarcoma, but not from less common forms of osteosarcoma or from several benign bone tumors. This case illustrates the low-grade osteoblastic histology, malignant osteoid formation, and medullary and surrounding soft tissue invasion diagnostic of intracortical osteosarcoma. The authors discuss the diagnostic difficulties presented by intracortical osteosarcoma and the natural history of these tumors. Int.J Surg Pathol 3(3):195-200, 1996