Clinical outcomes of an endoscopic transclival and transpetrosal approach for primary skull base malignancies involving the clivus

Restricted access


The endoscopic endonasal approach for treating primary skull base malignancies involving the clivus is a formidable task. The authors hypothesized that tumor involvement of nearby critical anatomical structures creates hurdles to endoscopic gross-total resection (GTR). The aim of this study was to retrospectively review the clinical outcomes of patients who underwent an endoscopic endonasal approach to treat primary malignancies involving the clivus and to analyze prognostic factors for GTR.


Between January 2009 and November 2015, 42 patients underwent the endoscopic endonasal approach for resection of primary skull base malignancies involving the clivus at 2 independent institutions. Clinical data; tumor locations within the clivus; and anatomical involvement of the cavernous or paraclival internal carotid artery, cisternal trigeminal nerve, hypoglossal canal, and dura mater were investigated to assess the extent of resection. Possible prognostic factors affecting GTR were also analyzed.


Of the 42 patients, 37 were diagnosed with chordomas and 5 were diagnosed with chondrosarcomas. The mean (± SD) preoperative tumor volume was 25.2 ± 30.5 cm3 (range 0.8–166.7 cm3). GTR was achieved in 28 patients (66.7%) and subtotal resection in 14 patients (33.3%). All tumors were classified as upper (n = 17), middle (n = 17), or lower (n = 8) clival tumors based on clival involvement, and as central (24 [57.1%]) or paramedian (18 [42.9%]) based on laterality of the tumor. Univariate analysis identified the tumor laterality (OR 6.25, 95% CI 1.51–25.86; p = 0.011) as significantly predictive of GTR. In addition, the laterality of the tumor was found to be a statistically significant predictor in multivariate analysis (OR 41.16, 95% CI 1.12–1512.65; p = 0.043).


An endoscopic endonasal approach can provide favorable clinical and surgical outcomes. However, the tumor laterality should be considered as a potential obstacle to total removal.

ABBREVIATIONS CN = cranial nerve; GTR = gross-total resection; ICA = internal carotid artery; STR = subtotal resection.

Article Information

Correspondence Doo-Sik Kong, Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Irwonro 81, Gangnam-gu, Seoul, 06351, Republic of Korea. email:

INCLUDE WHEN CITING Published online June 2, 2017; DOI: 10.3171/2016.12.JNS161920.

Drs. Y. H. Kim and C. Jeon contributed equally to this work.

Disclosures The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper.

© AANS, except where prohibited by US copyright law.



  • View in gallery

    Proposed sagittal classification of clival tumors involving the upper clivus (A), middle clivus (B), and lower clivus (C). Copyright Samsung Medical Center, Sungkyunkwan University. Published with permission. Figure is available in color online only.

  • View in gallery

    The dotted lines represent tangent planes that define the laterality of the clival tumors. Each plane includes the cavernous ICA, paraclival ICA, cisternal portion of the trigeminal nerve, and hypoglossal canal (A). Tumors within the bilateral tangential planes were regarded as midline tumors (central), whereas those involving or crossing the planes were regarded as laterally extended tumors (paramedian). An axial classification was proposed for those located within or extending beyond the paraclival ICA (B and E), cisternal portion of the trigeminal nerve (C and F), and hypoglossal canal (D and G). Copyright Samsung Medical Center, Sungkyunkwan University. Published with permission. Figure is available in color online only.

  • View in gallery

    Preoperative (A, B, E, and F) and postoperative (C, D, G, and H) Gd-enhanced T1-weighted MR scans. Case 20 (A–D): GTR of a centrally located chordoma on the upper clivus in a 53-year-old man with diplopia. Case 36 (E–H): STR of an upper and middle clivus chordoma extending beyond the left paraclival ICA into the left temporal lobe in a 36-year-old man with seizure. The patient developed a CN VI palsy after surgery.





All Time Past Year Past 30 Days
Abstract Views 184 184 24
Full Text Views 255 255 6
PDF Downloads 197 197 3
EPUB Downloads 0 0 0


Google Scholar