RESUMO
INTRODUCTION: Osteosarcoma, the second most frequent primary malignant bone tumor, is usually found in long bones: femur, tibia or humerus with only 6 to 7% of cases occurring in the jaws. Patients with osteosarcoma of the mandible usually complain of a swelling, which can be painful or not, accompanied by paresthesia of one of the trigeminal nerve branches in about 20% of cases. OBSERVATION: We report a case of chondroblastic osteosarcoma of the mandible affecting a 33-year-old woman with 14 years follow-up illustrating the difficulties of a rapid diagnosis. DISCUSSION: The prognosis of osteosarcoma of the mandible relies on its histological grade and the amount of time elapsing from diagnosis to treatment onset. The treatment of choice is radical surgery providing a 5-year survival rate up to 80%. The definitive surgical treatment is usually performed only after several interventions because operative-room pathology cannot be obtained due to the necessity of decalcification. In order to avoid multiple resections, an interim bridging with a reconstructive plate with a condylar head can be proposed before definitive graft reconstruction. The prognosis of osteosarcoma of the mandible is better than that of long bones. Chemotherapy or radiotherapy, which are very efficient for osteosarcoma in general, do not change the prognosis of osteosarcoma of the mandible.
