Dedifferentiated chondrosarcoma: our clinico-pathological experience and dilemmas in 25 cases.

BACKGROUND

Dedifferentiated chondrosarcoma represents a special form of the chondrosarcoma characterized by the presence of well-differentiated cartilaginous component in juxtaposition with the malignant mesenchymal tumor of high-malignancy grade.

METHODS

The study was performed on 25 tissue samples obtained by biopsy of the primary malignant bone tumors.

RESULTS

Out of the total of 25 patients, 13 were males and 12 were females. Their average age was 59.9 years (39-75). Radiological examination verified the presence of the pathological fractures in 14 patients. The skeletal distribution clearly indicates that the femur is the most frequent site of affection (in 15 patients--60%). Morphological analysis verified the presence of "precursor cartilaginous lesion" or low-grade cartilaginous component in all cases. Classification of the high-grade components was based on the immunohistochemical analyses, which evidenced MFH in 18 cases, osteosarcoma in 4, while fibrosarcoma was evidenced in 2 and rhabdomyosarcoma in 1 case. In 20 patients, out of whom 14 had existing fractures, amputation was indicated. In five patients (fracture-free), resection limb-salvage surgical intervention was performed.

CONCLUSION

The lethal outcome ensues within less than 2 years in all patients.