Chapter 18 – Chordomas and Chondrosarcomas of the Skull Base: Retrosigmoid Approaches

Abstract The surgical treatment of clivus chordomas and chondrosarcomas presents a challenge to neurosurgeons and ENT-surgeons. These tumors are rare and the complex anatomy of the clivus region and their infiltrative behavior make radical resection very difficult. Aggressive surgery with removal of the infiltrated bone is the treatment of choice. Several surgical approaches have been used. Recently, endoscopic approaches are increasingly used. Endoscopy permits a better visualization of the lesion but large dura defects are difficult to close with this technique. There is no postoperative curative therapy. Radiation therapy with proton beam and radiosurgery are indicated in the majority of cases. These tumors are refractory to currently used chemotherapy drugs. Better knowledge of the phenotype and molecular profile of these lesions may in the future help in the development of new target therapies.