Endoscopic Endonasal Resection of Clival Chordomas.

The endoscopic endonasal approach is a major step forward in the treatment of clival chordomas. It has improved the resection rate and in the same time reduced the complications. Chordomas located in the upper and mid-clival regions are well-suited for a purely endoscopic endonasal resection. Although with angulated endoscopes and curved high-speed drills, lateral parts of the tumor can be resected, lower clival lesions often necessitating a combination of both endonasal and transcranial approaches. A major limitation is a caudal tumor extension beyond the dens axis. For more caudally located lesions, a transoral approach might be needed. Since chordomas of the lower clivus may destroy the condyles or the dens axis, a posterior stabilization is frequently required in a second step of the surgery. Even though a gross total resection has been achieved, chordoma has the tendency to recur. Therefore, the current standard of care is postoperative proton or carbon ion radiation. Chemotherapy is not effective in classic chordomas, but has its place in poorly differentiated tumor which mostly occur in children. Recently, molecular targeted therapies have given hope for effective medical treatment options in the future.