Fibrosarcoma of the mandible: a diagnostic dilemma.

Fibrosarcoma is a malignant mesenchymal neoplasm of fibroblasts that rarely affects oral cavity and can cause local recurrences or metastasis. The aetiologic factors are still unknown, but many authors have reported the radiation therapy history as an important aetiological factor, followed by trauma and underlying conditions like Paget's disease, fibrous dysplasia or chronic osteomyelitis. Fibrosarcoma of mandible is rare, with an incidence which ranges from 0-6.1% of all primary fibrosarcomas of the bone. This paper has described a case of a swelling in the mandible of a 17-years old female who had a radiolucency in association with crown of an impacted tooth and foci of radiopacity, which led to a misdiagnosis of either an odontogenic lesion or a bone tumour, but proved to be a fibrosarcoma on histopathological and immunohistochemistry investigations.