Osteosarcoma of the mandible: analysis of nine cases.

A total of 16 cases of mandibular osteosarcoma were diagnosed histologically in Finland and reported to the Finnish Cancer Registry between 1953 and 1983. Review of the histologic slides confirmed the diagnosis in only nine cases. The overall five-year survival rate was 44%. Three patients who were free of clinical disease at the end of the follow-up period (mean, 9.9 years) either had tumors of low-grade malignancy (two cases) or had undergone prompt radical surgery (one case). The importance of radiography in the diagnosis of mandibular osteosarcoma is stressed, because the widening of the periodontal membrane spaces, the sunray effect, and the widening of the mandibular canal are almost pathognomonic for osteosarcoma.