[Cerebral primitive osteosarcoma, a radiological and histological atypia].

Introduction: Osteosarcoma is a malignant mesenchymal tumor including cells that present an osteoblastic differentiation. On the skull, it has often extra-axial development associated with bone reaction. We report an atypical and rare case of intracranial or cerebral osteosarcoma underline the radiological and pathological diagnostic difficulties.