AbstractBackground:Radiation therapy is a commonly used treatment in head and neck oncology, whether used alone or as an adjunct to other treatments. Osteoradionecrosis and radiation-induced malignancy are both rare, late complications of radiation therapy.Methods:This paper describes a case of radiation-induced sarcoma of the mandible initially presenting as osteoradionecrosis. In addition, the literature on the identification and treatment of these entities is reviewed.Results:The patient underwent excision and reconstruction of the presumed osteoradionecrosis. Final pathology demonstrated radiation-induced sarcoma. The patient suffered tumour recurrence at seven months post-operatively.Conclusion:When evaluating a patient with osteoradionecrosis, clinicians should be cognisant of the risk of malignancy. This paper describes the first case of radiation-induced sarcoma presenting as osteoradionecrosis. Primary treatment of radiation-induced sarcoma is wide surgical extirpation, with a very limited role for chemotherapy. Overall survival for this entity is poor.