Malignant transformation of craniomaxillofacial fibro-osseous lesions: A systematic review.

The purpose of this study was to perform a systematic review of the literature concerning all documented cases of malignant transformation of craniomaxillofacial fibro-osseous lesions (FOLs). Three electronic databases were searched. Data were evaluated descriptively. Kaplan-Meier survival curves were constructed and compared using the log-rank test. A critical appraisal of included articles was performed through the Joanna Briggs Institute tool. A total of 19 studies including 27 patients were selected for data extraction. Twenty-six cases were initially diagnosed as fibrous dysplasia and one as ossifying fibroma. The mean age at the time of malignant transformation was 38.11 years, and the average time from initial diagnosis to malignant transformation was 18.2 years. The male:female ratio was 1:1.2, and the maxilla:mandible ratio was 1.5:1. The histological type of the malignant tumor was predominantly osteosarcoma. Follow-up was available for 21 patients. The 3-year overall survival rate was 51%. Mandible tumors and diagnoses other than osteosarcoma tended to have poor survival rates, but no significant difference was identified. We concluded that between all FOLs, only fibrous dysplasia seems to have a considerable increased risk of malignant transformation. Thus, a regular and long follow-up period is advised.