Metastatic osteosarcoma to the squamous temporal bone with intra- and extracranial extension: A case report.

Background: Osteosarcoma is the most common malignant bone tumor in childhood and adolescence. Involvement of the skull is rare, and metastatic spread to the temporal bone has been scarcely described in the literature. In this case report, we present a patient with metastatic osteosarcoma to the squamous temporal bone who underwent successful tumor resection. Case Description: A 19-year-old male with a history of the left tibial osteosarcoma and multiple prior metastases treated with surgery and chemotherapy was admitted for nausea, somnolence, and headache. Imaging demonstrated a large osseous mass of the left squamous temporal bone with intracranial extension causing significant mass effect. He successfully underwent left radical mastoidectomy and left frontotemporal craniotomy for mass resection and cranioplasty. Histopathology confirmed the diagnosis of metastatic osteosarcoma. Conclusion: Osteosarcoma of the skull, particularly arising from metastatic spread, is rare. This case report demonstrates the efficacy of surgery as a means of local control, even in the setting of intracranial extension, and the benefit of multidisciplinary involvement in surgical planning and execution.