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 osteosarcoma (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 osteosarcomatous 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 analysis, 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.

Malignant Transformation of Ossifying Fibroma into Parosteal Osteosarcoma with High-grade Component: Presentation of an Unusual Case and Review of the Literature

Background:

Parosteal Osteosarcoma of the Jaw (POSJ) is a rare entity that is associated with a high survival rate. Several case reports and case series of POSJ have been published in the literature, but few authors have described development of this tumor by possible transformation from a fibro-osseous neoplasm.

Objective:

We present a rare occurrence of parosteal osteosarcoma with involvement of the posterior maxilla, orbit floor, and infra-temporal fossa in a 20-year-old man. Furthermore, we performed a literature review regarding clinical, radiological, and histological features; treatment strategies; and etiology/pathophysiology.

Methods:

A PubMed search yielded a total of 74 articles and the articles were sorted according to their corresponding key area of focus.

Results:

This was a case of POSJ with high-grade component in the maxillofacial region of a 20-year old male. Co-expression of MDM2 and CDK4 was confirmed. At 2.5-year follow-up, the patient had died. The literature review revealed 18 articles including 20 cases of POSJ. Four cases represent the possible development of this tumor by transformation from a fibro-osseous neoplasm: Two cases of fibrous dysplasia, one case of cemento-ossifying fibroma, and the case of Ossifying Fibroma (OF) in the present study.

Conclusion:

In conclusion, we found an unusual case of POSJ of the midface in a patient with a previous diagnosis of OF in the same region. To our knowledge, there have been no previous reports of development of POSJ in OF. Furthermore, this is the first described case of high-grade surface osteosarcoma in the craniofacial region.