Osteosarcomas of the jaws differ from their peripheral counterparts and require a distinct treatment approach. Experiences from the DOESAK Registry

Objective: We aim to emphasize crucial differences between osteosarcomas of the jaws (OSj) and those of the peripheral skeleton (OSp) and to question current therapeutic concepts in presenting a comprehensive study on 214 patients. Background: OSj account for only 6% of all osteosarcomas (OS) but seem to represent a clinically and prognostically distinct subgroup. Due to the limited experience with this rare disease it is still a matter of debate if (neo-)adjuvant chemotherapy can improve the outcome of patients like in OSp or if OSj patients can be cured by surgical treatment only. Methods: 214 well characterized OSj patients with long-term follow up are presented and the influence of clinico-pathological parameters affecting the prognosis of patients is discussed. Results: The OSj patients in our series showed metastatic spread far less frequently (17.6% of cases) and later in the course of the disease (26 months after diagnosis on average) compared to OSp. Consequently, complete resection of the tumors resulted in an excellent long-term survival (83.2% after 10 years). Neoadjuvant or adjuvant treatment applied in a smaller subset of patients, furthermore, failed to show any additional favorable effect. Conclusion: Whereas OSp is regarded as systemic disease at the time of diagnosis in which >90% of patients develop lung metastases without multimodality treatment, the vast majority of OSj patients seem to be curable by complete resection only. Based on the findings presented here, multimodality treatment should be critically scrutinized in OSj patients.