SDPS-05 ASSESSING SURVIVAL OUTCOMES AND COMPLICATION PROFILES FOLLOWING SURGICAL EXCISION OF SKULL BASE CHORDOMA: A COMPREHENSIVE SYSTEMATIC REVIEW AND META-ANALYSIS

Despite their precarious behavioral classification (histopathologically benign (low-grade), behaviorally malignant), great strides have been taken to improve prognostication and treatment paradigms for patients with skull base chordoma. However, due to the rarity of this tumor, prior investigations remain limited to small retrospective series. Accordingly, we performed a systematic review and meta-analysis in order to profile surgical and survival outcomes for skull base chordoma. Fixed and random-effect meta-analyses were performed for categorial variables including number of males, GTR, STR, 5-year OS, 10-year OS, 5-year PFS, and 10-year PFS. Following the systematic search and screen, 47 studies published between 1993-2020 reporting data for 2204 patients remained eligible for analysis. Sex distribution was comparable between males and females, with a slight predominance of male-identifying patients (0.5625 [0.5418;0.3909]). Average age at diagnosis was 42.4 ± 12.5 years, while average age of treatment initiation was 43.0 ± 10.6 years. Overall, there was a substantial degree of heterogeneity across the 47 studies (I^2=56.3% [44.0%; 65.9%]). With respect to operative margins, the rate of GTR was 0.3323 [0.2824; 0.3909], I^2 = 91.9% [90.2%; 93.4%], while the rate of STR was significantly higher at 0.5167 [0.4596; 0.5808], I^2 = 93.1% [91.6%; 94.4%]. Interestingly, 5-year OS rate was 0.7113 [0.6685; 0.7568], I^2 = 91.9% [90.0%; 93.5%]. Furthermore, 10-year OS rate was 0.4957 [0.4230; 0.5809], I^2 = 92.3% [89.2%; 94.4%], which was comparable to both 5-year PFS rate of 0.5054 [0.4394; 0.5813], I^2 = 84.2% [77.6%; 88.8%] and 10-yr PFS rate of 0.4949 [0.4075; 0.6010], I^2 = 14.9% [0.0%; 87.0%]. There were 55 reported deaths for a perioperative mortality rate of 2.5%. The most common complication was CSF leak(5.4%). Overall, these results indicate good 5-year outcomes; however, 10-year prognosis for skull base chordoma remains poor due to its radiotherapeutic resistance and high recurrence rate.