Rare Bone Sarcomas

Rare tumors of bone include chordoma, adamantinoma, hemangioendothelioma, hemangiopericytoma, low-grade fibrosarcoma of bone, and malignant fibrous histiocytoma (MFH). These are distinctive and interesting diseases with unique features. They bear some relationship to a spectrum of different mesenchymal tissues. Chordomas are probably derived from notochordal cells and thus are found primarily in the sacrum and sphenoocciput. Adamantinomas, on the other hand, are found predominantly in the tibia and show a peculiar tendency toward epithelial differentiation. The other tumors are more widely located within the body; hemangioendothelioma and hemangiopericytoma are tumors related to vascular tissue, whereas low-grade fibrosarcoma and MFH are most likely derived from spindle-shaped, fibroblast-like cells.