P12.09 * MALIGNANT TUMORS OF ANTERIOR SKULL BASE: IS THE ROLE OF SURGERY ENHANCED IN THE ENDOSCOPY ERA?

Abstract

INTRODUCTION: Malignant tumors of anterior skull base represent a surgical challenge because of their anatomical location, the necessity of achieving negative margins, and the often-cosmetically disfiguring transfacial approaches needed. Recently, expanded endonasal endoscopic approaches (EEEA) have been developed, either alone or combined with transcranial approaches for treatment of these malignant lesions. We report our experience to illustrate the relative safety and effectiveness of the EEEA for skull base malignancies alone or combined when possible with minimally invasive approaches or traditional surgery. METHODS: From June 2009, 13 patients harbouring malignant neoplastic lesions of anterior skull base were treated at our department. Four patients affected by sinonasal malignancies with extension in anterior cranial fossa underwent to combined open subfrontal or minimally invasive supra orbital approach and EEEA. In 2 patients with respectively esthesioneuroblastoma and maxillary sinus squamous cell carcinoma a combined supraorbital key-hole craniotomy and EEEA were perfomed. Seven clival metastases with VI cranial nerve palsy were approached by the EEEA supplemented by neuronavigation. RESULTS: Gross total removal was performed in 9 out of 13 patients. In the other cases partial resection, but with adequate decompression and diagnosis were achieved. There were no mortality, 1 patient had infection and 1 deep vein thrombosis. CONCLUSIONS: In our experience EEEA are an integral part of the neurosurgical armamentarium for the treatment of the skull base malignancies. In properly selected cases, it affords similar oncologic outcomes with lower morbidity than traditional open approaches. The major potential advantage of the EEEA approach is direct “natural” anatomical route to the lesion without traversing any major neurovascular structures, so obviating brain retraction. Many tumors grow in a medial-to-lateral direction, displacing structures laterally as they expand, creating natural corridors for their resection via an antero-medial approach. The complementary information provided by endoscopy can assist the surgeon in safely extend the approach maximizing the extent of resection and decompression in hidden angles. Nonetheless, these minimal access approaches should be considered a complement to well-established open approaches, which are still necessary in most advanced tumors.