The many faces of chondrosarcoma of bone, own cases and review of the literature with an emphasis on radiology, pathology and treatment.

Chondrosarcoma is the third most frequent primary malignant tumor of bone, constituting up to 16% of the malignant osseous neoplasms. Up to date several genetic alterations and markers were described concerning the pathogenesis and the progression of the chondrosarcoma, which represents actually a heterogeneous group of different types including conventional intramedullary, clear cell, myxoid, mesenchymal, and dedifferentiated chondrosarcoma. The pathologic appearance varies, however, in general they grow with a lobulated pattern. Histologically the hyaline cartilage demonstrates high water content and typically enchondral ossification is apparent. Imaging reflect this while radiographic findings suggest the diagnosis when the typical "ring-and-arc" chondroid matrix mineralization, endosteal scalloping and soft-tissue extension were apparent. The CT is used for detecting the mineralization of the matrix, especially when it is subtle or when the lesion is located in complex areas. MRT is the method of choice to detect the high water content of these lesions with a high signal intensity with T2-weighting and its bone marrow extend. Surgical resection is the primary and preferred treatment modality for most individuals with localized disease. In selected cases of the Grad I conventional chondrosarcoma curettage should be discussed. Systemic chemotherapy may be considered in variant forms such as mesenchymal or dedifferentiated chondrosarcomas. In knowledge of the "many faces" of the primary chondrosarcoma individualized patient assessment and optimal clinical management is possible.