Transoral vs. Endoscopic Endonasal Approach for Clival/Upper Cervical Chordoma

The surgical results of 18 cases of clival/upper cervical chordoma treated in the last decade via the endoscopic endonasal approach (EEA, 9 cases) and the transoral-transpalatal approach (TO-TPA, 9 cases) were compared. Each group showed the same incidence of subdural invasion, with 5 cases each. The superior (frontal base) and lateral surgical fields were wider by EEA, but the inferior view lower than the cranio-vertebral junction (CVJ) was wider by TO-TPA. Gross total removal was achieved in 3 cases in the EEA group, but in only 1 case in the TO-TPA group. Differences in radicality might be due to the extent of the lateral and subdural overview. However for large tumors extending below the CVJ, TO-TPA was the only viable approach for surgical removal. Surgical complications were higher in the EEA (4 cases) than the TO-TPA group (1 case), and were mainly caused by aggressive management of subdural invasion in the EEA group. Post-operative oral intake was earlier and the operative time was shorter in the EEA group. The surgical results were more radical and less invasive in the EEA group than the TO-TPA group. However in tumors extending below the CVJ, the surgical field in EEA was limited, indicating the need to use the transoral route or a combination of routes. A higher complication rate following subdural management was a negative factor that requires improvement in the EEA group and two-staged EEA followed by a transcranial approach may be considered for the cases with subdural invasion.