Malignant transformation of craniomaxillofacial fibro‐osseous lesions: A systematic review

Abstract

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.

Professional diagnostic delay in osteosarcomas of the jaws

“…Unfortunately, the paraffine blocks were not available anymore to perform such immunohistochemical stains in our two patients. There are various case reports and reviews of OSJ developing from fibrous dysplasia in low grade OSs ( 13 - 15 ). Probably some, if not many, of the reported cases have been an osteosarcoma right from the beginning as probably has been the case in our patient #2.…”

Malignant transformation of fibrous dysplasia into osteosarcoma confirmed with TP53 somatic mutation and mutational analysis of GNAS gene

“…Malignant transformation accounts for 0.4e1.0% of all FD cases. 6,7 A case series of 266 patients with a definitive diagnosis of FD in a Chinese population showed that malignant transformations only occurred in three patients with polyostotic forms. 7 Another case series from Mayo Clinic of 1122 cases with a histological diagnosis of FD had malignant transformations in 19 cases of monostotic FD and 9 cases of polyostotic FD.…”

“…8 The most common malignant changes are osteosarcoma, chondrosarcoma and fibrosarcoma. 6 Two case series have suggested a relationship with prior radiation, but most of the other case series have not investigated this relationship. 8,9 FD is associated with activating missense mutations in GNAS (20q13).…”

“…Of the 26 cases, only two case reports confirmed the presence of GNAS mutations in the malignant component. 6 Thus far, there are only two published reports addressing the presence or absence of GNAS mutations in the malignant component of transformed fibrous dysplasia, one in the femur and one in the maxilla. 4,5 Our case represents the third, also affecting the maxilla.…”

Common causes of ‘swelling’ in the oral cavity

“…6 Although uncommon, malignant transformation of fibrous dysplasia has been well described, and any sudden change in size of the lesion should alert the clinician to this possibility. 7 Ossifying fibroma is an uncommon lesion that presents with similar radiological characteristics to those of fibrous dysplasia, except that the margins are well defined. A more aggressive variant can be found in the paediatric population (juvenile aggressive ossifying fibroma), and the primary treatment for all forms of ossifying fibroma is surgical excision.…”