[Intracortical dedifferentiated chondrosarcoma].

Chondrosarcoma is the second most frequent mesenchymal malignant tumour of the bone. Classification of this kind of tumour is made by clinical, radiological und pathological means. A case of an intracortical chondrosarcoma was first reported by Babinet et al. 2003 [2]. During the staging examination of a 59-year-old patient referred to our clinic because of a squamous cell carcinoma of the oropharynx, we also found a highly malignant intracortical dedifferentiated chondrosarcoma of the distal femur shaft. Due to the primary assumption of bone metastasis of the oropharynx tumour, marginal extralesional tumour resection was performed followed by composite osteosynthesis. Considerations on differential diagnosis and their implications for further therapy are discussed.