Skull Base Chordoma: Long-Term Observation and Evaluation of Prognostic Factors after Surgical Resection

Abstract

Skull base chordoma (SBC) is relatively rare and data on its clinical outcome after surgical resection and adjuvant radiotherapy are still limited. Analyzing the clinical postoperative outcome of SBC patients and defining prognostic factors regarding current treatment modalities. In this study, 41 SBC patients from 2001 to 2017 were retrospectively analyzed in this single-center study. The most common clinical symptoms were headache (63%) and problems concerning vision (54%) like diplopia. The follow-up controls took place from 1 to 192 months. The mean survival time for the patients was 123.37 months (95% CI 90.89-155.86). The 5- and 10-year survival rates were 73.3 and 49%, respectively. Regarding the Karnofsky-Performance Scale (KPS), Cox regression showed a significant relationship between the survival rates in the overall study population and pre-surgery KPS (P = 0.004). This was further supported with a positive significant correlation between the pre-surgery KPS and the KPS at the last follow-up (P = 0.039). Statistical analysis showed that repeat surgical resection and radiotherapy could be prognostic factors. Furthermore, we were able to show that mortality decreased by 4.5% with each 10 points increase of pre-surgery KPS. This could be a major prognostic factor when deciding treatment modalities. Nevertheless, further standardized clinical studies with a larger patient population should be carried out to extrapolate prognostic factors and improve treatment modalities.