Juxtacortical Osteogenic Sarcoma of the Jaws: Case Report and Review of the Literature

Parosteal osteosarcoma of the mandible in a pediatric patient

Gnathic osteosarcoma is a rare malignant mesenchymal neoplasm showing evidence of osteoid matrix formation. Clinical behaviour and radiological appearances overlap with benign osseous lesions and are prone to misdiagnosis. Early diagnosis of osteosarcoma plays a crucial role in the treatment plan and prognosis. Herein a rare case of parosteal osteosarcoma of fibroblastic histologic subtype affecting the angle of the mandible in a 12-year-old female is presented.

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.

Parosteal osteosarcoma: Report of a rare juxtacortical variant of osteosarcoma affecting the maxilla

Parosteal osteosarcomas are rare, low-grade juxtacortical variant of osteosarcoma, especially in the jaws, representing 1.6% of all bony malignant tumours and upto 5% of all osteosarcomas. Only 12 cases of intraoral parosteal osteosarcomas have been reported in the English literature. In the jaws males are more commonly affected with peak occurrence at 39 years and nearly equal site predilection for maxilla and mandible. Radiographically, parosteal osteosarcomas are radiodense, lobulated masses with a broad stalk to the cortex of the bone with no periosteal reaction and medullary invasion. Microscopically, shows well-differentiated tumor with minimum atypia and rare mitotic figures separating trabeculae of woven bone. Unlike classical and periosteal osteosarcoma, it is considered to have a good prognosis. A case report of this rare entity in 22-year-old female patient with bony hard, painless swelling of 9 months duration in maxillary premolar-molar region is presented. The need for differential diagnostic approach is emphasized from other seemingly benign clinical entities.

Juxtacortical osteosarcoma of mandible

This article presents a case of juxtacortical (paraosteal) osteosarcoma in a 43-year-old female, which is rare malignant mesenchymal tumor. As per the literature, it accounts for less than 4% of all osteosarcomas. Due to its rare variety, this tumor can cause diagnostic dilemma and clinicians should be aware of it. Due to its clinical picture, it can be confused with peripheral fibro-osseous lesions. Success rate of treatment are good if the tumor is detected early and resected with wide margins giving a negligible chance for recurrence.