[Clear cell chondrosarcoma--clinico-pathological report of an additional case].

On account of the rarity and its histologic features, the clear-cell chondrosarcoma is a particular entity. Up to the present, 98 cases have been reported in the literature. In the present report one case located in the proximal femur will be discussed. Approximately 60% of these tumors are situated in the mentioned region. Including one referred case, which will not be described in detail, 100 cases have been recognized. Clear-cell chondrosarcoma is radiographically indistinguishable from benign lesions or chondroblastoma. Therefore the histologic examination is crucial for the diagnosis. The histologic characteristics preclude the diagnosis of chondroblastoma. Clear-cell chondrosarcoma is characterized by regions of chondroid matrix and areas of closely packed, glycogen-rich large tumor cells with distinct boundaries. The centrally located nuclei are large with marked polymorphism, surrounded by abundant clear PAS positive cytoplasm. The chondroid matrix is lacking. Osteoid formation and multinucleated giant cells are present in clear-cell areas. In spite of the low malignancy there is still a metastatic potential. Therefore the type of surgical treatment is very important. En bloc excision with wide margins is the treatment of choice. The knowledge about this tumor is crucial for adequate surgical therapy.