[Sarcoma arising in fibrous dysplasia: a clinicopathological analysis]

Objective: To study the clinicopathologic characteristics and risk factors of sarcoma arising in fibrous dysplasia. Methods: A total of 18 cases were collected from January 2008 to July 2018 in Shanghai Jiaotong University Affiliated Sixth People's Hospital. The characteristics and the histologic type were retrospectively reviewed. IBM SPSS 19 was used for statistical analysis. Results: The male to female ratio of patients with fibrodysplastic sarcomatosis was 1.57∶1.00. The age of onset ranged from 24 to 87 years (mean 49 years). The long bones, especially the femur, were most frequently involved. Nine cases were osteosarcomas, three cases were high grade sarcoma and six cases were low grade sarcoma. Logistic regression analysis showed that age was an independent risk factor for sarcomatous change, compared with polyostotic or recurrent cases. Value of Wals was 13.61 (P<0.05), and odds ratio was 12.82,95% confidence interval was 3.31-49.70. Conclusions: Fibrodysplasia sarcomatosis is clinically nonspecific and the risk of sarcomatous changes increases approximately 12-fold when age of onset of fibrous dysplasia is over 40 years.