Chondroblastoma, which is histologically composed of mononuclear cell proliferation and lobules of immature cartilage, and chondromyxoid fibroma, which is composed of myxoid lobules with spindle or stellate cells and a cellular fibrous rim with spindle cells, are both rare tumors. Based on histogenetic investigation including immunohistochemistry, matrix biochemistry, and electron microscopy, chondroblastoma is thought to contain chondrogenic cells, whereas chondromyxoid fibroma is considered to...