Intracortical osteosarcoma. A case report.

Abstract

Intracortical osteosarcoma (IO) is the rarest form of osteosarcoma. A 19-year-old man had one of these lesions in the upper diaphysis of the femur. Microscopically, IO was a well-differentiated osteosarcoma with an osteoblastic histologic pattern. The typical location in the diaphysis and the peculiar histologic and roentgenographic findings with intracortical origin clearly separate this entity from conventional osteosarcomas as well as periosteal and parosteal osteosarcomas. IO are lytic neoplasms confined to the cortex of the diaphysis with a benign roentgenographic appearance, but are included in the differential diagnosis of benign tumors.