Sinonasal teratocarcinosarcoma treated via endonasal endoscopic approach and CyberKnife radiotherapy: A case report and review of the literature

Teratocarcinosarcoma is an extremely invasive high-grade malignancy that develops in the nasal cavity and paranasal sinus, with pathological features of both teratoma and carcinosarcoma. Here, we present a case of primary teratocarcinosarcoma in the sphenoid sinus along with a review of the literature. A 70-year-old woman presented to our hospital with chief complaints of diplopia, photophobia in the right eye, and dull pain in the back of the right eyeball. Ophthalmological examination showed no abnormalities, and head magnetic resonance imaging showed a tumoral lesion extending from the sella turcica to the sphenoid sinus. Endonasal endoscopic removal of the malignant tumor was performed under general anesthesia. Intraoperative findings revealed that the posterior wall of the sphenoid sinus had thinned out because of compression by the tumor, which had adhered to the dura mater and internal carotid artery. This made total excision difficult, and the tumor was removed as much as possible. Based on pathological examination, the tumor was diagnosed as a teratocarcinosarcoma. Since postoperative magnetic resonance imaging suggested the presence of residual tumor, irradiation was administered at a dose of 36 Gy in 12 fractions with CyberKnife. Subjective symptoms, including diplopia, showed improvement, and imaging showed regression of the lesion. The patient has had an uneventful course without recurrence for 40 months. Maximal safe excision via endonasal endoscopic approach combined with the use of CyberKnife is a potentially useful and minimally invasive treatment method for teratocarcinosarcoma in the sphenoid sinus.