[Clear-cell chondrosarcoma of the bone]

Data on the macroscopic features and histological structure of clear-cell chondrosarcoma of the bone obtained in studies on 15 tumors are presented. The most typical element of the histological picture consists of peculiar "clear" cells containing glycogen inclusions. The tumor cells produce interstitial cartilage substance and osteoid as well as primitive slightly atypical bone structures. Electron microscopic examinations performed in 5 tumors revealed "clear" cells, the cells of the type occurring in chondrosarcomas and chondroblastomas, and multinuclear giant cells. Morphological features of the clear-cell chondrosarcomas allow them to be considered as a special type of malignant bone tumors. They differ from the known kinds of chondrosarcomas and somewhat resemble chondroblastomas and chondroblastic osteogenic sarcomas. The possibility of secondary origin of the tumor on the basis of malignization of chondroblastoma is discussed.