A review of imaging of surface sarcomas of bone

Abstract

Surface lesions of bone are uncommon. Although their imaging features generally mirror those of their intramedullary counterparts, surface lesions may demonstrate distinct characteristics which along with their unusual location present a diagnostic challenge. Surface sarcomas are usually of a lower grade compared with intramedullary variants, leading to differences in management. Osteosarcoma arising from the cortical surface of the bone is termed juxtacortical or surface osteosarcoma and includes three distinct entities: parosteal, periosteal, and high-grade surface osteosarcoma. We also review the features intracortical osteosarcoma, which some authors include under the umbrella term surface osteosarcoma. These lesions exhibit biologic features distinct from those of conventional intramedullary osteosarcoma, which underlines the importance of accurate imaging diagnosis. Periosteal chondrosarcoma and periosteal Ewing sarcoma also have distinctive imaging appearances. The purpose of this article is to review surface sarcomas of bone with regard to their clinical and radiological features and to discuss the differential diagnosis for each condition.

Keywords: High-grade surface osteosarcoma; Intracortical osteosarcoma; Juxtacortical chondrosarcoma; Parosteal osteosarcoma; Periosteal Ewing sarcoma; Periosteal chondrosarcoma; Periosteal osteosarcoma; Surface lesions; Surface osteosarcoma; Surface sarcoma; Surface tumors.