Also found in: Dictionary, Thesaurus, Encyclopedia.
Related to periosteal osteosarcoma: parosteal osteosarcoma
chondroblastic osteosarcoma occurring on the surface of bones without involvement of the marrow; usually presents in adolescents and young adults as a lucent defect with bone spicules extending into soft tissues. Histologically, the tumor is intermediate to high grade, and the cartilage is lobulated.
periosteal osteosarcomaAn uncommon (less than 2%) osteosarcoma (OS) with the same demographic as conventional OS. It is related to periosteal chondrosarcoma, and usually arises in diaphysis of the proximal tibia or distal femur.
Small radiolucencies on bone surface with bone spicules perpendicular to shaft and penetrating soft tissues; no medullary involvement.
Parosteal chondrosarcoma—lobules of malignant cartilage with calcification and surface endochondral ossification, no malignant osteoid.
Intermediate between high-grade and parosteal (juxtacortical) OSs or chondrosarcoma; high local recurrence; 15% metastasise.