Clinical characteristics, immunohistochemistry, and outcomes of 77 patients with skull base chordomas

To analyze the clinical characteristics, immunohistochemistry, and treatment outcomes for skull base chordomas and the correlation between extent of resection/pathology type and outcomes.

The clinical materials of 77 consecutive patients with skull base chordomas were analyzed retrospectively. Follow-up data were available in 66 patients, ranging from 6 to 142 months (mean, 59.6 months). Outcome in survival was assessed by the overall survival (OS) and progression-free survival (PFS). Outcome in function was evaluated by Karnofsky performance score.

Total or near-total tumor resection was achieved in 25 cases (32.5%), subtotal in 32 cases (47.6%), and partial resection in 9 cases (11.7%). Gamma knife radiosurgery was used in 22 patients (33.3%). Forty-two of the 77 patients had immunohistochemistry results and the rates of positive staining for cytokeratin, epithelial membrane antigen, vimentin, S-100 were 100%, 92.9%, 83.3%, and 88.1%, respectively. The PFS rates at 3, 5, and 8 years were 82.6%, 45.0%, and 18.2%, respectively. The OS rates at 3, 5, and 8 years were 89.2%, 70.9%, and 45.5 %, respectively. Less tumor resection and dedifferentiated pathology were risk factors for worse OS and PFS (P < 0.05). Among the 43 currently surviving patients, the mean Karnofsky performance score before the surgery and at the last follow-up were 87.3 and 82.4, respectively.

Aggressive surgical resection should be performed for skull base chordomas, considering certain postoperative functional status. Immunohistochemical study is helpful in differential diagnosis. The combination of aggressive surgical resection and gamma knife radiosurgery for skull base chordomas may obtain favorable outcomes.