Frequency of spontaneous osteosarcomatous transformation of craniofacial fibrous dysplasia: a systematic review

Objective. A systematic review was undertaken to examine the spontaneous of craniofacial fibrous dysplasia (FD) into osteosar-coma (OS). Study Design. Five databases were searched, and data were evaluated in 2 subsets: (1) frequency analysis involving only cross-sectional studies that specifically examined patients for osteosarcomatous transformation, thereby allowing a calculation of the frequency of transformation of craniofacial FD, and (2) case analysis of case reports and case series of FD that underwent osteosar-comatous transformation. Quality assessment of the studies in the frequency and case analyses was performed. Results. Seven cross-sectional studies involving 779 patients in the frequency analysis documented transformation of craniofacial FD into OS in 13 patients, for a frequency of 1.67%. Of the 18 separate cases of osteosarcomatous transformation in the case anal-ysis, 11 (61.1%) occurred in females, 11 (61.1%) developed from monostotic FD, and 7 (38.9%) arose in the mandible, with 5 in the maxilla (27.8%) and 6 (33.3%) in other craniofacial sites. The mean age of the patients at the time of malignant diagnosis was 36.4 years, with an average of 11.3 years from FD diagnosis to the appearance of OS. The quality of the articles ranged from fair to excellent. Conclusions. The risk of osteosarcomatous transformation of craniofacial FD is low, but the possibility of transformation should be taken into consideration by clinicians, as this will guide treatment and follow-up regimens. (Oral Surg Oral Med Oral Pathol Oral Radiol 2023;135:678-685)