Lack of efficacy of neoadjuvant chemotherapy in adult patients with maxillo-facial high-grade osteosarcomas: A French experience in two reference centers.

Introduction: Neoadjuvant chemotherapy (neo-CT) for osteosarcomas is the standard of care. Management of maxillo-facial osteosarcomas (MFOS) is challenging. In this rare disease, we collected a large cohort of patients with the aim to report the histological and radiological local response rates to neo-CT.