Chondrosarcoma of the mandible. Case report.

Chondrosarcoma is a malignant tumour derived from cartilaginous cells. It accounts for 10-12% of all malignant bone tumours and it is the second more common bone tumour after osteosarcoma. However, it rarely occurs in the bones of the visceralcranium. The majority of head and neck chondrosarcomas occur in the upper or lower jaw, with a slightly higher incidence in the upper jaw. Especially, the temporomandibular joint (TMJ) is a rare location. Case report: Α rare case of a large chondrosarcoma of the mandible, developed on an osteochondroma of the mandibular condyle is presented, and the most interesting and unusual pathology results are discussed. A 70-year-old woman presented with a hard painless swelling on the right side of her face, related to the mandibular condyle. A biopsy of the lesion revealed an osteochondroma. The patient refused to undergo the proposed surgical operation, but returned to our hospital after 18 months, with a large tumour mass resultingin facial asymmetry and difficulties in chewing and speaking. The tumour was surgically removed. Microscopically, it was a chondrosarcoma, grade II to III. In acertain part, foci of undifferentiated chondrosarcoma were also present. The undifferentiated component displayed histological features of a malignant fibrous histiocytoma developed on a large osteochondroma.