To evaluate the relationships between mutations of the p53 and MDM-2 proteins in human primary chondrosarcoma and in secondary chondrosarcoma from osteochondromatosis.

From January, 1984 to April, 2000, 33 cases were grouped into three categories: Group I, osteochondromatosis (18 cases), group II, secondary chondrosarcoma (6 cases), group III, primary chondrosarcoma (9 cases). We analysed the expressions of the p53 and MDM-2 proteins. All specimens were embedded in paraffin and stained using the Streptavidin-Biotin peroxidase method with anti-p53 antibody, and DO7 anti-MDM-2 antibody IF2 as monoclonal antibody.

The expressions of the p53 and MDM-2 proteins, the pathologic grade of each group, and clinical outcomes were compared and analysed. The expressions of the p53 and MDM-2 proteins in each group were significantly different (p<0.05). However, MDM-2 protein expression was similar between group II and III. Both p53 and MDM-2 protein were expressed most frequently in group III and this was significant. There was an increased manifestation of the p53 and MDM-2 protein in the higher pathologic grade. The 5-year survival rate of patients with a malignant tumor was about 70%. In expired patients, the histologic grade was grade III, and both proteins were expressed, which enabled a relationship to be established between p53 and MDM-2 protein expression and a poorer prognosis.

In osteochondromatosis, the coexpression of the p53 and MDM-2 proteins was not observed, but isolated p53 or MDM-2 expression was observed in some cases. According to this study, it is helpful as a basic study for early detection of malignant translation of osteochondromatosis. In conclusion, we suggest that the expressions of the p53 and MDM-2 proteins are useful indicators of prognosis.