Liposarcoma of the Petrous Bone: Unusual Localization of Sarcoma: About Case

Malignant tumors of the ear are uncommon and may arise from multiple anatomical compartments, leading to heterogeneous clinical presentations and management strategies. Lesions of the external auditory canal (EAC) can mimic refractory otitis externa, warranting biopsy when symptoms persist despite appropriate medical therapy. We report the case of a 55-year-old woman with a history of thigh liposarcoma previously treated with radiotherapy who presented with hearing loss and right temporo-occipital headaches. Otoscopic examination revealed an exophytic mass obstructing the right EAC. MRI demonstrated a 46 × 32 mm mixed osseous–soft tissue mass involving the right petrous temporal bone and posterior skull base, with extension into the tympanic cavity and EAC, invasion of adjacent soft tissues including the parotid space, and cervical epidural extension to C4 causing mild spinal cord compression without radiologic myelopathy. Vascular involvement was prominent, with tumor thrombus in the right transverse/sigmoid sinus and internal jugular vein, collateral venous extension, and encasement/invasion of the right vertebral artery, which remained patent. Biopsy confirmed dedifferentiated liposarcoma with a minimal heterologous osteosarcomatous component, consistent with the patient’s known disease. Given the extent and critical skull base involvement, the patient was treated with definitive radiotherapy. This case highlights the diagnostic challenge of EAC masses, the importance of early biopsy in atypical or treatment-resistant presentations, and the complexity of achieving local control for head and neck sarcomas where wide surgical margins are often not feasible.