Endoscopic versus Open Clival Chordoma Resection: A Systematic Review

Objective: Microscope-based surgical approaches to the clivus require large openings to allow the passage of sufficient light to the lateral extent of clival chordomas, and have traditionally utilized extensive bone drilling, brain retraction, and manipulation of cranial nerves that lie along the operative trajectory. A ventral approach to the tumor is a more logical trajectory, but transoral approaches are limited by the hard palate, and transfacial approaches may be cosmetically undesirable. The endoscopic transclival approach represents a new paradigm in surgical philosophy, offering a minimal access, maximally aggressive alternative that may be preferable in a subgroup of patients. We performed a systematic analysis of the literature to assess the efficacy and complications of this approach compared with more standard cranial base approaches.

Methods: We performed a MEDLINE search for the years 1950–2010 to identify relevant studies. Comparisons were made between open and endoscopic series for patient and tumor characteristics as well as recurrence, survival, and mortality. Statistical analyses of categorical variables were undertaken using chi-square and Fisher's exact tests.

Results: Forty-six studies, involving 778 patients, were included. Compared with the open surgery cohort, the endoscopic cohort had a significantly higher percentage of gross total resection (60.8% vs. 48.1%, P = 0.010), fewer cranial nerve deficits (2.5% vs. 24.1%, P = 0.0001), fewer incidences of meningitis (0.9% vs. 5.9%, P = 0.030), less mortality (4.6% vs. 21.7%, P = 0.0001), and fewer local recurrences (16.9% vs. 40.0%, P = 0.0001). There was no significant difference in the incidence of postoperative CSF leak (P = 0.077). Follow-up was longer in the open compared with the endoscopic cohort (59.7 vs. 18.2 months).

Conclusion: Our systematic analysis supports the endonasal endoscopic approach as a safe and effective alternative to traditional open cranial base surgery for the treatment of certain clival chordomas. For carefully selected small midline tumors, it is likely preferable. Although the overall literature supports the use of this technique, longer follow-up is needed to more definitively address therapeutic efficacy. Nevertheless, the advent of this new approach signals a paradigm shift in the surgical management of these difficult tumors.