Chondrosarcoma of the temporomandibular joint. A case report and review of the literature.

Chondrosarcoma is a malignant tumor characterized by the formation of cartilage, but not bone, by tumor cells. Only 5% to 10% of chondrosarcomas occur in the head and neck, representing 0.1% of all head and neck neoplasms, with the larynx and the maxillo-nasal region being the most common sites. This report describes an unusual case of chondrosarcoma in a 54-year-old man who presented with pain and swelling in the left preauricular area. Computed tomography demonstrated a soft tissue mass in the left temporomandibular joint without causing erosion of the adjacent bony structures. The tumor was treated by excision in a single block with perilesional tissues, preserving the facial nerve. Histopathologic examination revealed chondrocytes with irregular nuclei with S-100 immunocytochemical staining positive in 30% of the tumor. The diagnosis was a grade I chondrosarcoma. There was no evidence of disease at the 16-month follow-up. The occurrence of chondrosarcoma in the temporomandibular joint (TMJ) is an exceptional event, with only 16 cases described. We report a case of this unusual entity and review the literature.