Radiation-induced intracranial osteosarcoma of the anterior skull base after treatment of esthesioneuroblastoma.

Esthesioneuroblastoma (ENB) is an uncommon sinonasal cancer of the olfactory neuroepithelium that is typically treated with surgical resection followed by radiation therapy. Radiation-induced intracranial osteosarcoma of the skull base is a rare but devastating long-term complication of radiation therapy in this region. Here, we present a case of an 82-year-old patient who developed radiation-induced osteosarcoma of the anterior skull base and paranasal sinuses 10 years after radiation therapy following resection of an ENB. Older patients may be at risk of developing this complication earlier and with a worse prognosis relative to younger patients. Treating physicians/surgeons should be aware of this devastating complication. Patients who are treated with high-dose radiation therapy in this region should be followed for many years.